Intelligent robot cleaner for setting travel route based on video learning and managing method thereof

ABSTRACT

An intelligent robot cleaner setting a travel path based on a video learning includes a travel driver, a suction unit, an image acquisition unit, and a controller. The travel driver moves to an area to be cleaned along the travel path. The suction unit sucks foreign substances on the travel path. The image acquisition unit acquires an image on the travel path. The controller analyzes the image, decides whether an object is present on the travel path, classifies a type of the object, and sets a bypass travel path that avoids the object if the object is an avoidance object.

TECHNICAL FIELD

The present invention relates to an intelligent robot cleaner forsetting a travel path based on video learning and a method of managingthe same, and more particularly to an intelligent robot cleaner and amethod of managing the same capable of effectively coping with anobstacle in an area to be cleaned according to a result of artificialintelligent learning.

BACKGROUND ART

A robot cleaner sucks dust and foreign substances on a floorcorresponding to an area to be cleaned while moving along apredetermined travel path. A travel path through which the robot cleanermoves is set in advance. Since various obstacles may exist on the travelpath, measures are sought to cope with the obstacles.

To cope with the obstacles, in a related art, it was common to identifythe obstacles that obstruct the movement of the robot cleaner and set atravel path by bypassing the corresponding obstacles.

However, various obstacles may exist in the area to be cleaned inaddition to obstacles that obstruct the movement of the robot cleaner.For example, as the number of users living with companion animalsincreases, the number of companion animal feces increases in the area tobe cleaned. Since contaminants such as companion animal feces do notinterfere with the movement of the robot cleaner, the related art robotcleaner moves on the area with the contaminants on the travel path.Hence, there arises a problem that the area to be cleaned becomes moredifficult to clean. Alternatively, since small-sized valuables, etc. donot interfere with the movement of the robot cleaner, the robot cleanersucks the valuables, etc. in the process of cleaning along a fixedtravel path. As described above, as the robot cleaner moves withoutrecognizing them as an obstacle, the area to be cleaned may be furthermessed up or there is a risk of losing valuables.

Alternatively, even if an obstacle on the travel path is an object thatdoes not obstruct the movement of the robot cleaner, the robot cleanermay avoid the obstacle. Hence, there is a disadvantage that the cleaningis performed insufficiently.

DISCLOSURE Technical Problem

An object of the present invention is to address the above-described andother problems.

Another object of the present disclosure is to provide a robot cleanerand a method of managing the same capable of recognizing an obstaclethat obstructs a movement of the robot cleaner.

Another object of the present disclosure is to provide a robot cleanerand a method of managing the same capable of finding an obstacle thatmay interfere with the cleaning and avoiding the obstacle.

Another object of the present disclosure is to provide a robot cleanerand a method of managing the same capable of solving a disadvantage thatthe cleaning is carried out insufficiently due to an error of avoidingan object that does not obstruct a movement of the robot cleaner.

Technical Solution

In one aspect of the present invention, there is provided an intelligentrobot cleaner setting a travel path based on a video learning comprisinga travel driver, a suction unit, an image acquisition unit, and acontroller. The travel driver moves to an area to be cleaned along thetravel path. The suction unit sucks foreign substances on the travelpath. The image acquisition unit acquires an image on the travel path.The controller analyzes the image, decides whether an object is presenton the travel path, classifies a type of the object, and sets a bypasstravel path that avoids the object if the object is an avoidance object.

The intelligent robot cleaner setting the travel path based on the videolearning according to an embodiment of the present invention may furthercomprise a memory storing image information of the avoidance object.

The controller according to an embodiment of the present invention maycheck whether an image feature of an object extracted from the image ismatched to image information of the avoidance object stored in thememory.

The memory according to an embodiment of the present invention maystore, as the image information of the avoidance object, an image of atleast one of an immovable object, a fragile object, a viscous or liquidcontaminant, or a no-suction object.

The controller according to an embodiment of the present invention mayclassify the object as an ignorance object if the object does not belongto the avoidance object, and maintain the travel path.

The controller according to an embodiment of the present invention maymaintain the travel path if the object is a movable object due to themovement of the robot cleaner.

The intelligent robot cleaner setting the travel path based on the videolearning according to an embodiment of the present invention may furthercomprise an event output unit outputting an event that the avoidanceobject has been found if the controller finds the avoidance object.

The intelligent robot cleaner setting the travel path based on the videolearning according to an embodiment of the present invention may furthercomprise a user input unit receiving a processing instructioncorresponding to the event.

If the event is output and then an instruction of ignoring the avoidanceobject is received from the user input unit, the controller according toan embodiment of the present invention may control the travel driver sothat the travel driver travels on an area in which the avoidance objectis found.

If the event is output and then a processing instruction for theavoidance object is not received from the user input unit for apredetermined period of time, the controller according to an embodimentof the present invention may set the bypass travel path.

If the controller decides the object as the no-suction object, thecontroller according to an embodiment of the present invention maystore, in the memory, a name and location information of the no-suctionobject in the acquired image.

In another aspect of the present invention, there is provided a methodof managing an intelligent robot cleaner setting a travel path based ona video learning, the method comprising acquiring an image on the travelpath, analyzing the image and deciding whether an object is present onthe travel path, classifying a type of the object if the object ispresent, and setting a bypass travel path that bypasses the travel pathif the classified object is an avoidance object.

The classifying of the type of the object according to an embodiment ofthe present invention may be determined based on a result of learningthe acquired image.

The classifying of the object according to an embodiment of the presentinvention may comprise classifying the object as the avoidance object ifthe object is an immovable object, a fragile object, a viscous or liquidcontaminant, or a no-suction object.

The classifying of the object according to an embodiment of the presentinvention may further comprise classifying the object as the avoidanceobject or an ignorance object and classifying the object as theignorance object if the object does not belong to the avoidance object,and maintaining the travel path if the classified object is theignorance object.

The classifying of the object according to an embodiment of the presentinvention may further comprise classifying the object as the ignoranceobject if the object is a movable object due to the movement of therobot cleaner.

The method of managing the intelligent robot cleaner according to anembodiment of the present invention may further comprise, if the objectis the avoidance object, outputting an event that the avoidance objecthas been found.

The method of managing the intelligent robot cleaner according to anembodiment of the present invention may further comprise, afteroutputting the event that the avoidance object has been found, preparingto receive a processing instruction corresponding to the event.

The method of managing the intelligent robot cleaner according to anembodiment of the present invention may further comprise, if theprocessing instruction corresponding to the event is an instruction ofignoring the avoidance object, traveling on an area in which theavoidance object is found.

The method of managing the intelligent robot cleaner according to anembodiment of the present invention may further comprise, if theprocessing instruction corresponding to the event is not received for apredetermined period of time, setting the bypass travel path.

The method of managing the intelligent robot cleaner according to anembodiment of the present invention may further comprise, if the objectis classified as the no-suction object in the classifying of the object,storing a name and location information of the no-suction object.

Advantageous Effects

Effects of a multi-device control system and a method thereof accordingto the present invention are described as follows.

The present invention can efficiently control the travel of a robotcleaner by recognizing an obstacle, that obstructs a movement of therobot cleaner, based on the image reading and moving by avoiding theobstacle.

The present invention can also increase a cleaning performance of arobot cleaner by finding an obstacle, that may disturb the robot cleanerand an area to be cleaned, and avoiding the obstacle.

The present invention can also solve a disadvantage that the cleaning isperformed insufficiently by reading an object that can be pushed by arobot cleaner and performing the cleaning.

DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram of a wireless communication system to whichthe methods proposed herein may be applied.

FIG. 2 shows an example of a basic operation of an user equipment and a5G network in a 5G communication system.

FIG. 3 illustrates an example of application operation of an userequipment and a 5G network in a 5G communication system.

FIGS. 4 to 7 show an example of an operation of an user equipment using5G communication.

FIG. 8 is a diagram illustrating an example of a 3GPP signaltransmission/reception method.

FIG. 9 illustrates an SSB structure and FIG. 10 illustrates SSBtransmission.

FIG. 11 illustrates an example of a random access procedure.

FIG. 12 shows an example of an uplink grant.

FIG. 13 shows an example of a conceptual diagram of uplink physicalchannel processing.

FIG. 14 shows an example of an NR slot in which a PUCCH is transmitted.

FIG. 15 is a block diagram of a transmitter and a receiver for hybridbeamforming.

FIG. 16 shows an example of beamforming using an SSB and a CSI-RS.

FIG. 17 is a flowchart illustrating an example of a DL BM process usingan SSB.

FIG. 18 shows another example of DL BM process using a CSI-RS.

FIG. 19 is a flowchart illustrating an example of a process ofdetermining a reception beam of a UE.

FIG. 20 is a flowchart illustrating an example of a transmission beamdetermining process of a BS.

FIG. 21 shows an example of resource allocation in time and frequencydomains related to an operation of FIG. 21.

FIG. 22 shows an example of a UL BM process using an SRS.

FIG. 23 is a flowchart illustrating an example of a UL BM process usingan SRS.

FIG. 24 is a diagram showing an example of a method of indicating apre-emption.

FIG. 25 shows an example of a time/frequency set of pre-emptionindication.

FIG. 26 shows an example of a narrowband operation and frequencydiversity.

FIG. 27 is a diagram illustrating physical channels that may be used forMTC and a general signal transmission method using the same.

FIG. 28 is a diagram illustrating an example of scheduling for each ofMTC and legacy LTE.

FIG. 29 shows an example of a frame structure when a subcarrier spacingis 15 kHz.

FIG. 30 shows an example of a frame structure when a subscriber spacingis 3.75 kHz.

FIG. 31 shows an example of a resource grid for NB-IoT uplink.

FIG. 32 shows an example of an NB-IoT operation mode.

FIG. 33 is a diagram illustrating an example of physical channels thatmay be used for NB-IoT and a general signal transmission method usingthe same.

FIGS. 34 and 35 illustrate a robot cleaner according to an embodiment ofthe present invention.

FIG. 36 is a block diagram illustrating configuration of a robot cleaneraccording to an embodiment of the present invention.

FIG. 37 illustrates an AI device according to an embodiment of thepresent invention.

FIG. 38 is a flow chart illustrating a first embodiment of a method ofmanaging a robot cleaner.

FIG. 39 illustrates a method, by a robot cleaner, for selecting a travelpath on a cleaning map.

FIG. 40 illustrates an example of an image acquired by an imageacquisition unit.

FIG. 41 illustrates an example of setting a bypass travel path.

FIG. 42 is a flow chart illustrating a second embodiment of a method ofmanaging a robot cleaner.

FIG. 43 illustrates an example of a method of informing of an avoidanceobject.

FIG. 44 illustrates a method for identifying a lost article using arobot cleaner.

FIG. 45 illustrates a management system of a robot cleaner according toanother embodiment.

MODE FOR INVENTION

Hereinafter, embodiments of the disclosure will be described in detailwith reference to the attached drawings. The same or similar componentsare given the same reference numbers and redundant description thereofis omitted. The suffixes “module” and “unit” of elements herein are usedfor convenience of description and thus may be used interchangeably anddo not have any distinguishable meanings or functions. Further, in thefollowing description, if a detailed description of known techniquesassociated with the present invention would unnecessarily obscure thegist of the present invention, detailed description thereof will beomitted. In addition, the attached drawings are provided for easyunderstanding of embodiments of the disclosure and do not limittechnical spirits of the disclosure, and the embodiments should beconstrued as including all modifications, equivalents, and alternativesfalling within the spirit and scope of the embodiments.

While terms, such as “first”, “second”, etc., may be used to describevarious components, such components must not be limited by the aboveterms. The above terms are used only to distinguish one component fromanother.

When an element is “coupled” or “connected” to another element, itshould be understood that a third element may be present between the twoelements although the element may be directly coupled or connected tothe other element. When an element is “directly coupled” or “directlyconnected” to another element, it should be understood that no elementis present between the two elements.

The singular forms are intended to include the plural forms as well,unless the context clearly indicates otherwise.

In addition, in the specification, it will be further understood thatthe terms “comprise” and “include” specify the presence of statedfeatures, integers, steps, operations, elements, components, and/orcombinations thereof, but do not preclude the presence or addition ofone or more other features, integers, steps, operations, elements,components, and/or combinations.

A. Example of Autonomous Vehicle and 5G Network

FIG. 1 is a block diagram of a wireless communication system to whichmethods proposed in the disclosure are applicable.

Referring to FIG. 1, a device including an autonomous driving module isdefined as a first communication device (910 of FIG. 1 and see paragraphN for detailed description), and a processor 911 may perform detailedautonomous driving operations.

Another vehicle or a 5G network communicating with the autonomousdriving device is defined as a second communication device (920 of FIG.1, and see paragraph N for details), and a processor 921 may performdetailed autonomous driving operations.

Details of a wireless communication system, which is defined asincluding a first communication device, which is an autonomous vehicle,and a second communication device, which is a 5G network, may refer toparagraph N.

B. AI Operation Using 5G Communication

FIG. 2 shows an example of a basic operation of a user equipment and a5G network in a 5G communication system.

The UE transmits the specific information transmission to the 5G network(S1).

Then, the 5G network performs 5G processing on the specific information(S2).

In this connection, the 5G processing may include AI processing.

Then, the 5G network transmits a response including the AI processingresult to the UE (S3).

FIG. 3 shows an example of application operation of a user terminal anda 5G network in a 5G communication system.

The UE performs an initial access procedure with the 5G network (S20).The initial connection procedure will be described in more detail inparagraph F.

Then, the UE performs a random access procedure with the 5G network(S21). The random access procedure will be described in more detail inparagraph G.

The 5G network transmits an UL grant for scheduling transmission ofspecific information to the UE (S22). The process of the UE receivingthe UL grant will be described in more detail in the ULtransmission/reception operation in paragraph H.

Then, the UE transmits specific information to the 5G network based onthe UL grant (S23).

Then, the 5G network performs 5G processing on the specific information(S24).

In this connection, the 5G processing may include AI processing.

Then, the 5G network transmits a DL grant for scheduling transmission ofthe 5G processing result of the specific information to the UE (S25).

Then, the 5G network transmits a response including the AI processingresult to the UE based on the DL grant (S26).

In FIG. 3, an example in which the AI operation and the initialconnection process, or the random access process and the DL grantreception process are combined with each other has been exemplarilydescribed using the S20 to S26. However, the present invention is notlimited thereto.

For example, the initial connection process and/or the random accessprocess may be performed using the process of S20, S22, S23, S24, andS24. In addition, the initial connection process and/or the randomaccess process may be performed using, for example, the process of S21,S22, S23, S24, and S26. Further, the AI operation and the downlink grantreception procedure may be combined with each other using the process ofS23, S24, S25, and S26.

C. UE Operation Using 5G Communication

FIG. 4 to FIG. 7 show an example of the operation of the UE using 5Gcommunication.

Referring first to FIG. 4, the UE performs an initial access procedurewith the 5G network based on SSB to obtain DL synchronization and systeminformation (S30).

Then, the UE performs a random access procedure with the 5G network forUL synchronization acquisition and/or UL transmission (S31).

Then, the UE receives an UL grant to the 5G network to transmit specificinformation (S32).

Then, the UE transmits the specific information to the 5G network basedon the UL grant (S33).

Then, the UE receives a DL grant for receiving a response to thespecific information from the 5G network (S34).

Then, the UE receives a response including the AI processing result fromthe 5G network based on the DL grant (S35).

A beam management (BM) process may be added to S30. A beam failurerecovery process may be added to S31. A quasi-co location relationshipmay be added to S32 to S35. A more detailed description thereof will bedescribed in more detail in paragraph I.

Next, referring to FIG. 5, the UE performs an initial access procedurewith the 5G network based on SSB to obtain DL synchronization and systeminformation (S40).

Then, the UE performs a random access procedure with the 5G network forUL synchronization acquisition and/or UL transmission (S41).

Then, the UE transmits the specific information to the 5G network basedon a configured grant (S42). A procedure for configuring the grant inplace of receiving the UL grant from the 5G network will be described inmore detail in paragraph H.

Then, the UE receives a DL grant for receiving a response to thespecific information from the 5G network (S43).

Then, the UE receives the response including the AI processing resultfrom the 5G network based on the DL grant (S44).

Next, referring to FIG. 6, the UE performs an initial access procedurewith the 5G network based on the SSB to obtain DL synchronization andsystem information (S50).

Then, the UE performs a random access procedure with the 5G network forUL synchronization acquisition and/or UL transmission (S51).

Then, the UE receives a DownlinkPreemption IE from the 5G network (S52).

The UE receives a DCI format 2_1 including a preamble indication fromthe 5G network based on the DownlinkPreemption IE (S53).

Then, the UE does not perform (or expect or assume) the reception of theeMBB data using a resource (PRB and/or OFDM symbol) indicated by thepre-emption indication (S54).

The operation related to the preemption indication is described in moredetail in paragraph J.

Then, the UE receives an UL grant to the 5G network to transmit thespecific information (S55).

Then, the UE transmits the specific information to the 5G network basedon the UL grant (S56).

Then, the UE receives a DL grant for receiving a response to thespecific information from the 5G network (S57).

Then, the UE receives a response including the AI processing result fromthe 5G network based on the DL grant (S58).

Next, referring to FIG. 7, the UE performs an initial access procedurewith the 5G network based on SSB to obtain DL synchronization and systeminformation (S60).

Then, the UE performs a random access procedure with the 5G network forUL synchronization acquisition and/or UL transmission (S61).

Then, the UE receives an UL grant to the 5G network to transmit thespecific information (S62).

The UL grant includes information on the number of repetitions oftransmission of the specific information. The specific information isrepeatedly transmitted based on the information on the repetition number(S63).

The UE transmits the specific information to the 5G network based on theUL grant.

Then, the iterative transmission of the specific information isperformed using the frequency hopping. The first transmission of thespecific information may be done using a first frequency resource, andthe second transmission of the specific information may be done using asecond frequency resource.

The specific information may be transmitted over a narrow band of 6RB(Resource Block) or 1RB (Resource Block).

Then, the UE receives a DL grant for receiving a response to thespecific information from the 5G network (S64).

Then, the UE receives a response including the AI processing result fromthe 5G network based on the DL grant (S65).

The mMTC described in FIG. 7 will be described in more detail in theparagraph K.

D. Introduction

Hereinafter, downlink (DL) refers to communication from a base station(BS) to user equipment (UE), and uplink (UL) refers to communicationfrom a UE to a BS. In the downlink, a transmitter may be part of the BSand a receiver may be part of the UE. In the uplink, a transmitter maybe part of the UE and a receiver may be part of the BS. Herein, the UEmay be represented as a first communication device and the BS may berepresented as a second communication device. The BS may be replacedwith a term such as a fixed station, a Node B, an evolved NodeB (eNB), anext generation nodeB (gNB), a base transceiver system (BTS), an accesspoint (AP), a network or a 5G (5th generation), artificial intelligence(AI) system, a road side unit (RSU), robot, and the like. Also, the UEmay be replaced with a terminal, a mobile station (MS), a user terminal(UT), a mobile subscriber station (MSS), a subscriber station (SS), anadvanced mobile station (AMS), a wireless terminal (WT), a machine-typecommunication (MTC) device, a machine-to-machine (M2M) device, adevice-to-device (D2D) device, a vehicle, a robot, an AI module, and thelike.

Techniques described herein may be used in a variety of wireless accesssystems such as Code Division Multiple Access (CDMA), Frequency DivisionMultiple Access (FDMA), Time Division Multiple Access (TDMA), OrthogonalFrequency Division Multiple Access (OFDMA), Single Carrier FrequencyDivision Multiple Access (SC-FDMA), etc. CDMA may be implemented as aradio technology such as Universal Terrestrial Radio Access (UTRA) orCDMA2000. TDMA may be implemented as a radio technology such as GlobalSystem for Mobile communications (GSM)/General Packet Radio Service(GPRS)/Enhanced Data Rates for GSM Evolution (EDGE). OFDMA may beimplemented as a radio technology such as IEEE 802.11 (Wi-Fi), IEEE802.16 (WiMAX), IEEE 802.20, Evolved-UTRA (E-UTRA) etc. UTRA is a partof Universal Mobile Telecommunications System (UMTS). 3rd GenerationPartnership Project (3GPP) Long Term Evolution (LTE) is a part ofEvolved UMTS (E-UMTS) using E-UTRA. LTE-Advanced (LTE-A)/LTE-A pro is anevolution of 3GPP LTE. 3GPP NR NR(New Radio or New Radio AccessTechnology) is an evolution of 3GPP LTE/LTE-A/LTE-A pro.

For clarity, the following description focuses on a 3GPP communicationsystem (e.g., LTE-A, NR), but technical features of the presentinvention is not limited thereto. LTE refers to technology after 3GPP TS36.xxx Release 8. In detail, LTE technology after 3GPP TS 36.xxx Release10 is referred to as LTE-A, and LTE technology after 3GPP TS 36.xxxRelease 13 is referred to as LTE-A pro. 3GPP 5G (5th generation)technology refers to technology after TS 36.xxx Release 15 andtechnology after TS 38.XXX Release 15. The technology after TS 38.xxxRelease 15 may be referred to as 3GPP NR, and technology after TS 36.xxxRelease 15 may be referred to as enhanced LIE. “xxx” refers to astandard document detail number. LTE/NR may be collectively referred toas a 3GPP system.

In this disclosure, a node refers to a fixed point capable oftransmitting/receiving a radio signal through communication with a UE.Various types of BSs may be used as nodes irrespective of the termsthereof. For example, a BS, a node B (NB), an e-node B (eNB), apico-cell eNB (PeNB), a home eNB (HeNB), a relay, a repeater, etc. maybe a node. In addition, the node may not be a BS. For example, the nodemay be a radio remote head (RRH) or a radio remote unit (RRU). The RRHor RRU generally has a power level lower than a power level of a BS. Atleast one antenna is installed per node. The antenna may refer to aphysical antenna or refer to an antenna port, a virtual antenna, or anantenna group. A node may be referred to as a point.

In this specification, a cell refers to a prescribed geographical areato which one or more nodes provide a communication service. A “cell” ofa geographic region may be understood as coverage within which a nodecan provide a service using a carrier and a “cell” of a radio resourceis associated with bandwidth (BW) which is a frequency range configuredby the carrier. Since DL coverage, which is a range within which thenode is capable of transmitting a valid signal, and UL coverage, whichis a range within which the node is capable of receiving the validsignal from the UE, depends upon a carrier carrying the signal, coverageof the node may be associated with coverage of “cell” of a radioresource used by the node. Accordingly, the term “cell” may be used toindicate service coverage by the node sometimes, a radio resource atother times, or a range that a signal using a radio resource can reachwith valid strength at other times.

In this specification, communicating with a specific cell may refer tocommunicating with a BS or a node which provides a communication serviceto the specific cell. In addition, a DL/UL signal of a specific cellrefers to a DL/UL signal from/to a BS or a node which provides acommunication service to the specific cell. A node providing UL/DLcommunication services to a UE is called a serving node and a cell towhich UL/DL communication services are provided by the serving node isespecially called a serving cell. Furthermore, channel status/quality ofa specific cell refers to channel status/quality of a channel orcommunication link formed between a BS or node which provides acommunication service to the specific cell and a UE.

Meanwhile, a “cell” associated with radio resource may be defined as acombination of DL resources and UL resources, that is, a combination ofa DL component carrier (CC) and a UL CC. A cell may be configured to bea DL resource alone or a combination of DL resources and UL resources.If carrier aggregation is supported, a linkage between a carrierfrequency of a DL resource (or DL CC) and a carrier frequency of a ULresource (or UL CC) may be indicated by system information transmittedthrough a corresponding cell. Here, the carrier frequency may be thesame as or different from a center frequency of each cell or CC.Hereinafter, a cell operating at a primary frequency will be referred toas a primary cell (Pcell) or a PCC, and a cell operating at a secondaryfrequency will be referred to as a secondary cell (Scell) Or SCC. TheScell may be configured after the UE performs a radio resource control(RRC) connection establishment with the BS to establish an RRCconnection therebetween, that is, after the UE is RRC_CONNECTED. Here,RRC connection may refer to a channel through which an RRC of the UE andan RRC of the BS may exchange RRC messages with each other. The Scellmay be configured to provide additional radio resources to the UE.Depending on the capabilities of the UE, the Scell may form a set ofserving cells for the UE together with the Pcell. In the case of a UEwhich is in the RRC_CONNECTED state but is not configured in carrieraggregation or does not support carrier aggregation, there is only oneserving cell that is only configured as the Pcell.

Cells support unique wireless access technologies. For example,transmission/reception according to LTE radio access technology (RAT) isperformed on an LTE cell, and transmission/reception according to 5G RATis performed on a 5G cell.

A carrier aggregation (CA) system refers to a system for supporting awide bandwidth by aggregating a plurality of carriers each having anarrower bandwidth than a target bandwidth. A CA system is differentfrom OFDMA technology in that DL or UL communication is performed usinga plurality of carrier frequencies each of which forms a systembandwidth (or a channel bandwidth), whereas the OFDM system carries abase frequency band divided into a plurality of orthogonal subcarrierson a single carrier frequency to perform DL or UL communication. Forexample, in the case of OFDMA or orthogonal frequency divisionmultiplexing (OFDM), one frequency band having a constant systembandwidth is divided into a plurality of subcarriers having a certainsubscriber spacing, and information/data is mapped in the plurality ofsubcarriers, and the frequency band to which the information/data ismapped is unconverted and transmitted as a carrier frequency of thefrequency band. In the case of wireless carrier aggregation, frequencybands having their own system bandwidth and carrier frequency may besimultaneously used for communication, and each frequency band used forcarrier aggregation may be divided into a plurality of subcarriershaving a predetermined subcarrier spacing.

The 3GPP-based communication standard defines DL physical channelscorresponding to resource elements carrying information derived from ahigher layer of a physical layer (e.g., a medium access control (MAC)layer, a radio link control (RLC) layer, a packet data convergenceprotocol (PDCP) layer, a radio resource control (RRC) layer, a servicedata adaptation protocol (SDAP), and a non-access stratum (NAS) layerand DL physical signals corresponding to resource elements which areused by a physical layer but which do not carry information derived froma higher layer. For example, a physical downlink shared channel (PDSCH),a physical broadcast channel (PBCH), a physical multicast channel(PMCH), a physical control format indicator channel (PCFICH), and aphysical downlink control channel (PDCCH) are defined as the DL physicalchannels, and a reference signal and a synchronization signal aredefined as the DL physical signals. A reference signal (RS), also calleda pilot, refers to a special waveform of a predefined signal known toboth a BS and a UE. For example, a cell-specific RS (CRS), a UE-specificRS, a positioning RS (PRS), channel state information RS (CSI-RS), and ademodulation reference signal (DMRS) may be defined as DL RSs.Meanwhile, the 3GPP-based communication standards define UL physicalchannels corresponding to resource elements carrying information derivedfrom a higher layer and UL physical signals corresponding to resourceelements which are used by a physical layer but which do not carryinformation derived from a higher layer. For example, a physical uplinkshared channel (PUSCH), a physical uplink control channel (PUCCH), and aphysical random access channel (PRACH) are defined as the UL physicalchannels, and a demodulation reference signal (DM RS) for a ULcontrol/data signal and a sounding reference signal (SRS) used for ULchannel measurement are defined as the UL physical signals.

In this specification, a physical downlink control channel (PDCCH) and aphysical downlink shared channel (PDSCH) may refer to a set of atime-frequency resources or a set of resource elements carrying downlinkcontrol information (DCI) and downlink data, respectively. In addition,a physical uplink control channel, a physical uplink shared channel(PUSCH), and a physical random access channel refer to a set of atime-frequency resources or a set of resource elements carrying uplinkcontrol information (UCI), uplink data and random access signals,respectively. Hereinafter, UE's transmitting an uplink physical channel(e.g., PUCCH, PUSCH, or PRACH) means transmitting UCI, uplink data, or arandom access signal on the corresponding uplink physical channel orthrough then uplink physical channel. BS's receiving an uplink physicalchannel may refer to receiving DCI, uplink data, or random access signalon or through the uplink physical channel. BS's transmitting a downlinkphysical channel (e.g., PDCCH and PDSCH) has the same meaning astransmitting DCI or downlink data on or through the correspondingdownlink physical channel. UE's receiving a downlink physical channelmay refer to receiving DCI or downlink data on or through thecorresponding downlink physical channel.

In this specification, a transport block is a payload for a physicallayer. For example, data given to a physical layer from an upper layeror a medium access control (MAC) layer is basically referred to as atransport block.

In this specification, HARQ (Hybrid Automatic Repeat and reQuest) is akind of error control method. HARQ-acknowledgement (HARQ-ACK)transmitted through the downlink is used for error control on uplinkdata, and HARQ-ACK transmitted on the uplink is used for error controlon downlink data. A transmitter that performs the HARQ operationtransmits data (e.g., a transport block, a codeword) and waits for anacknowledgment (ACK). A receiver that performs the HARQ operation sendsan acknowledgment (ACK) only when data is properly received, and sends anegative acknowledgment (NACK) if an error occurs in the received data.The transmitter may transmit (new) data if ACK is received, andretransmit data if NACK is received. After the BS transmits schedulinginformation and data according to the scheduling information, a timedelay occurs until the ACK/NACK is received from the UE andretransmission data is transmitted. This time delay occurs due tochannel propagation delay and a time taken for data decoding/encoding.Therefore, when new data is sent after the current HARQ process isfinished, a blank space occurs in the data transmission due to the timedelay. Therefore, a plurality of independent HARQ processes are used toprevent generation of the blank space in data transmission during thetime delay period. For example, if there are seven transmissionoccasions between an initial transmission and retransmission, thecommunication device may operate seven independent HARQ processes toperform data transmission without a blank space. Utilizing the pluralityof parallel HARQ processes, UL/DL transmissions may be performedcontinuously while waiting for HARQ feedback for a previous UL/DLtransmission.

In this specification, channel state information (CSI) refers toinformation indicating quality of a radio channel (or a link) formedbetween a UE and an antenna port. The CSI may include at least one of achannel quality indicator (CQI), a precoding matrix indicator (PMI), aCSI-RS resource indicator (CRI), an SSB resource indicator (SSBRI), alayer indicator (LI), a rank indicator (RI), or a reference signalreceived power (RSRP).

In this specification, frequency division multiplexing (FDM) may referto transmission/reception of signals/channels/users at differentfrequency resources, and time division multiplexing (TDM) may refer totransmission/reception of signals/channels/users at different timeresources.

In the present invention, a frequency division duplex (FDD) refers to acommunication scheme in which uplink communication is performed on anuplink carrier and downlink communication is performed on a downlinkcarrier wave linked to the uplink carrier, and time division duplex(TDD) refers to a communication scheme in which uplink and downlinkcommunications are performed by dividing time on the same carrier.

For background information, terms, abbreviations, etc. used in thepresent specification, may refer to those described in standarddocuments published before the present invention. For example, thefollowing document may be referred:

GPP LTE

-   -   3GPP TS 36.211: Physical channels and modulation    -   3GPP TS 36.212: Multiplexing and channel coding    -   3GPP TS 36.213: Physical layer procedures    -   3GPP TS 36.214: Physical layer; Measurements    -   3GPP TS 36.300: Overall description    -   3GPP TS 36.304: User Equipment (UE) procedures in idle mode    -   3GPP TS 36.314: Layer 2—Measurements    -   3GPP TS 36.321: Medium Access Control (MAC) protocol    -   3GPP TS 36.322: Radio Link Control (RLC) protocol    -   3GPP TS 36.323: Packet Data Convergence Protocol (PDCP)    -   3GPP TS 36.331: Radio Resource Control (RRC) protocol    -   3GPP TS 23.303: Proximity-based services (Prose); Stage 2    -   3GPP TS 23.285: Architecture enhancements for V2X services    -   3GPP TS 23.401: General Packet Radio Service (GPRS) enhancements        for Evolved Universal Terrestrial Radio Access Network (E-UTRAN)        access    -   3GPP TS 23.402: Architecture enhancements for non-3GPP accesses    -   3GPP TS 23.286: Application layer support for V2X services;        Functional architecture and information flows    -   3GPP TS 24.301: Non-Access-Stratum (NAS) protocol for Evolved        Packet System (EPS); Stage 3    -   3GPP TS 24.302: Access to the 3GPP Evolved Packet Core (EPC) via        non-3GPP access networks; Stage 3    -   3GPP TS 24.334: Proximity-services (ProSe) User Equipment (UE)        to ProSe function protocol aspects; Stage 3    -   3GPP TS 24.386: User Equipment (UE) to V2X control function;        protocol aspects; Stage 3 3GPP NR    -   3GPP TS 38.211: Physical channels and modulation    -   3GPP TS 38.212: Multiplexing and channel coding    -   3GPP TS 38.213: Physical layer procedures for control    -   3GPP TS 38.214: Physical layer procedures for data    -   3GPP TS 38.215: Physical layer measurements    -   3GPP TS 38.300: NR and NG-RAN Overall Description    -   3GPP TS 38.304: User Equipment (UE) procedures in idle mode and        in RRC inactive state    -   3GPP TS 38.321: Medium Access Control (MAC) protocol    -   3GPP TS 38.322: Radio Link Control (RLC) protocol    -   3GPP TS 38.323: Packet Data Convergence Protocol (PDCP)    -   3GPP TS 38.331: Radio Resource Control (RRC) protocol    -   3GPP TS 37.324: Service Data Adaptation Protocol (SDAP)    -   3GPP TS 37.340: Multi-connectivity; Overall description    -   3GPP TS 23.287: Application layer support for V2X services;        Functional architecture and information flows    -   3GPP TS 23.501: System Architecture for the 5G System    -   3GPP TS 23.502: Procedures for the 5G System    -   3GPP TS 23.503: Policy and Charging Control Framework for the 5G        System; Stage 2    -   3GPP TS 24.501: Non-Access-Stratum (NAS) protocol for 5G System        (5GS); Stage 3    -   3GPP TS 24.502: Access to the 3GPP 5G Core Network (5GCN) via        non-3GPP access networks    -   3GPP TS 24.526: User Equipment (UE) policies for 5G System        (5GS); Stage 3

E. 3GPP Signal Transmission/Reception Method

FIG. 8 is a diagram illustrating an example of a 3GPP signaltransmission/reception method.

Referring to FIG. 8, when a UE is powered on or enters a new cell, theUE performs an initial cell search operation such as synchronizationwith a BS (S201). For this operation, the UE can receive a primarysynchronization channel (P-SCH) and a secondary synchronization channel(S-SCH) from the BS to synchronize with the BS and acquire informationsuch as a cell ID. In LTE and NR systems, the P-SCH and S-SCH arerespectively called a primary synchronization signal (PSS) and asecondary synchronization signal (SSS). The initial cell searchprocedure is described in detail in paragraph F. below.

After initial cell search, the UE can acquire broadcast information inthe cell by receiving a physical broadcast channel (PBCH) from the BS.Further, the UE can receive a downlink reference signal (DL RS) in theinitial cell search step to check a downlink channel state.

After initial cell search, the UE can acquire more detailed systeminformation by receiving a physical downlink shared channel (PDSCH)according to a physical downlink control channel (PDCCH) and informationincluded in the PDCCH (S202).

Meanwhile, when the UE initially accesses the BS or has no radioresource for signal transmission, the UE can perform a random accessprocedure (RACH) for the BS (steps S203 to S206). To this end, the UEcan transmit a specific sequence as a preamble through a physical randomaccess channel (PRACH) (S203 and S205) and receive a random accessresponse (RAR) message for the preamble through a PDCCH and acorresponding PDSCH (S204 and S206). In the case of a contention-basedRACH, a contention resolution procedure may be additionally performed.The random access procedure is described in detail in paragraph G.below.

After the UE performs the above-described process, the UE can performPDCCH/PDSCH reception (S207) and physical uplink shared channel(PUSCH)/physical uplink control channel (PUCCH) transmission (S208) asnormal uplink/downlink signal transmission processes. Particularly, theUE receives downlink control information (DCI) through the PDCCH

The UE monitors a set of PDCCH candidates in monitoring occasions setfor one or more control element sets (CORESET) on a serving cellaccording to corresponding search space configurations. A set of PDCCHcandidates to be monitored by the UE is defined in terms of search spacesets, and a search space set may be a common search space set or aUE-specific search space set. CORESET includes a set of (physical)resource blocks having a duration of one to three OFDM symbols. Anetwork can configure the UE such that the UE has a plurality ofCORESETs. The UE monitors PDCCH candidates in one or more search spacesets. Here, monitoring means attempting decoding of PDCCH candidate(s)in a search space. When the UE has successfully decoded one of PDCCHcandidates in a search space, the UE determines that a PDCCH has beendetected from the PDCCH candidate and performs PDSCH reception or PUSCHtransmission on the basis of DCI in the detected PDCCH.

The PDCCH can be used to schedule DL transmissions over a PDSCH and ULtransmissions over a PUSCH. Here, the DCI in the PDCCH includes downlinkassignment (i.e., downlink grant (DL grant)) related to a physicaldownlink shared channel and including at least a modulation and codingformat and resource allocation information, or an uplink grant (ULgrant) related to a physical uplink shared channel and including amodulation and coding format and resource allocation information.

F. Initial Access (IA) Process

Synchronization signal block (SSB) transmission and related operation

FIG. 9 illustrates an SSB structure. The UE can perform cell search,system information acquisition, beam alignment for initial access, andDL measurement on the basis of an SSB. The SSB is interchangeably usedwith a synchronization signal/physical broadcast channel (SS/PBCH) bloc.

Referring to FIG. 9, the SSB includes a PSS, an SSS and a PBCH. The SSBis configured in four consecutive OFDM symbols, and a PSS, a PBCH, anSSS/PBCH or a PBCH is transmitted for each OFDM symbol. Each of the PSSand the SSS includes one OFDM symbol and 127 subcarriers, and the PBCHincludes 3 OFDM symbols and 576 subcarriers. The PBCH is encoded/decodedon the basis of a polar code and modulated/demodulated according toquadrature phase shift keying (QPSK). The PBCH in the OFDM symbolincludes data resource elements (REs) to which a complex modulationvalue of a PBCH is mapped and DMRS REs to which a demodulation referencesignal (DMRS) for the PBCH is mapped. There are three DMRS REs perresource block of the OFDM symbol, and there are three data REs betweenthe DMRS REs.

Cell Search

Cell search refers to a process in which a UE acquires time/frequencysynchronization of a cell and detects a cell identifier (ID) (e.g.,physical layer cell ID (PCI)) of the cell. The PSS is used to detect acell ID in a cell ID group and the SSS is used to detect a cell IDgroup. The PBCH is used to detect an SSB (time) index and a half-frame.

The cell search procedure of the UE may be summarized as shown in Table1 below.

TABLE 1 Type of Signals Operations 1st step PSS SS/PBCH block (SSB)symbol timing acquisition Cell ID detection within a cell ID group(3hypothesis) 2nd Step SSS Cell ID group detection (336 hypothesis) 3rdStep PBCH SSB index and Half frame (HF) index DMRS (Slot and frameboundary detection) 4th Step PBCH Time information (80 ms, System FrameNumber (SFN), SSB index, HF) Remaining Minimum System Information (RMSI)Control resource set (CORESET)/ Search space configuration 5th StepPDCCH and Cell access information PDSCH RACH configuration

There are 336 cell ID groups and there are 3 cell IDs per cell ID group.A total of 1008 cell IDs are present. Information on a cell ID group towhich a cell ID of a cell belongs is provided/acquired through an SSS ofthe cell, and information on the cell ID among 336 cell ID groups isprovided/acquired through a PSS.

FIG. 10 illustrates SSB transmission.

The SSB is periodically transmitted in accordance with SSB periodicity.A default SSB periodicity assumed by a UE during initial cell search isdefined as 20 ms. After cell access, the SSB periodicity can be set toone of {5 ms, 10 ms, 20 ms, 40 ms, 80 ms, 160 ms} by a network (e.g., aBS). An SSB burst set is configured at a start portion of the SSBperiod. The SSB burst set includes a 5 ms time window (i.e.,half-frame), and the SSB may be transmitted up to N times within the SSburst set. The maximum transmission number L of the SSB may be given asfollows according to a frequency band of a carrier wave. One slotincludes a maximum of two SSBs.

-   -   For frequency range up to 3 GHz, L=4    -   For frequency range from 3 GHz to 6 GHz, L=8    -   For frequency range from 6 GHz to 52.6 GHz, L=64

A time position of an SSB candidate in the SS burst set may be definedaccording to a subscriber spacing. The SSB candidate time position isindexed from 0 to L−1 (SSB index) in time order within the SSB burst set(i.e., half-frame).

A plurality of SSBs may be transmitted within a frequency span of acarrier wave. Physical layer cell identifiers of these SSBs need not beunique, and other SSBs may have different physical layer cellidentifiers.

The UE may acquire the DL synchronization by detecting the SSB. The UEmay identify a structure of the SSB burst set on the basis of thedetected SSB (time) index and thus detect a symbol/slot/half-frameboundary. The number of the frame/half-frame to which the detected SSBbelongs may be identified using system frame number (SFN) informationand half-frame indication information.

Specifically, the UE may acquire a 10-bit SFN for a frame to which thePBCH belongs from the PBCH. Next, the UE may acquire 1-bit half-frameindication information. For example, if the UE detects a PBCH with ahalf-frame indication bit set to 0, it may determine that the SSB, towhich the PBCH belongs, belongs to a first half-frame in the frame, andif the UE detects a PBCH with a half-frame indication bit set to 1, itmay determine that the SSB, to which the PBCH belongs, belongs to asecond half-frame in the frame. Finally, the UE may acquire an SSB indexof the SSB to which the PBCH belongs on the basis of a DMRS sequence andPBCH payload carried by the PBCH.

Acquisition of System Information (SI)

SI is divided into a master information block (MIB) and a plurality ofsystem information blocks (SIBs). The SI other than the MIB may bereferred to as remaining minimum system information (RMSI). Detailsthereof may be referred to the following:

-   -   The MIB includes information/parameters for monitoring the PDCCH        scheduling PDSCH carrying system information block1 (SIB1) and        is transmitted by the BS through the PBCH of the SSB. For        example, the UE may check whether a control resource set        (CORESET) exists for the Type 0-PDCCH common search space on the        basis of the MIB. The Type 0-PDCCH common search space is a kind        of PDCCH search space and is used to transmit a PDCCH for        scheduling an SI message. If the Type 0-PDCCH common search        space is present, the UE may determine (i) a plurality of        contiguous resource blocks and one or more consecutive resource        blocks constituting a CORESET on the basis of information in the        MIB (e.g., pdcch-ConfigSIB1) and (ii) a PDCCH occasion (e.g.,        time domain position for PDCCH reception). If no Type 0-PDCCH        common search space exists, pdcch-ConfigSIB1 provides        information on a frequency location where SSB/SIB1 exists and        information on a frequency range where SSB/SIB1 does not exist.    -   SIB1 includes information related to availability and scheduling        (e.g., transmission periodicity and SI-window size) of the        remaining SIBs (hereinafter, SIBx, x is an integer equal to or        greater than 2). For example, SIB1 may indicate whether the SIBx        is periodically broadcast or provided according to a request        from the UE on an on-demand basis. If SIBx is provided on the        on-demand basis, SIB1 may include information necessary for the        UE to perform the SI request. The SIB1 is transmitted through        the PDSCH, the PDCCH for scheduling the SIB1 is transmitted        through the Type 0-PDCCH common search space, and the SIB1 is        transmitted through the PDSCH indicated by the PDCCH.    -   The SIBx is included in the SI message and transmitted via the        PDSCH. Each SI message is transmitted within a time window        (i.e., SI-window) that occurs periodically.

G. Random Access Procedure

The random access procedure of the UE may be summarized as shown inTable 2 and FIG. 11.

TABLE 2 Signal type Acquired operation/information First PRACH preambleAcquire initial beam step in UL Random selection of random accesspreamble ID Second Random access Timing advance information stepresponse on Random access preamble ID PDSCH Initial UL grant, temporaryC-RNTI Third UL transmission RRC connection request step on PUSCH UEidentifier Fourth Contention Temporary C-RNTI on PDCCH for stepresolution on DL initial access C-RNTI on PDCCH for RRC_CONNECTED UE

The random access procedure is used for various purposes. For example,the random access procedure can be used for network initial access,handover, and UE-triggered UL data transmission. A UE can acquire ULsynchronization and UL transmission resources through the random accessprocedure. The random access procedure is classified into acontention-based random access procedure and a contention-free randomaccess procedure.

FIG. 11 illustrates an example of a random access procedure. Inparticular, FIG. 11 illustrates a contention-based random accessprocedure.

First, a UE can transmit a random access preamble through a PRACH asMsg1 of a random access procedure in UL.

Random access preamble sequences having different two lengths aresupported. A long sequence length 839 is applied to subcarrier spacingsof 1.25 kHz and 5 kHz and a short sequence length 139 is applied tosubcarrier spacings of 15 kHz, 30 kHz, 60 kHz and 120 kHz.

Multiple preamble formats are defined by one or more RACH OFDM symbolsand different cyclic prefixes (and/or guard time). RACH configurationfor a cell is included in the system information of the cell and isprovided to the UE. The RACH configuration includes information on asubcarrier spacing of the PRACH, available preambles, preamble format,and the like. The RACH configuration includes association informationbetween SSBs and RACH (time-frequency) resources. The UE transmits arandom access preamble in the RACH time-frequency resource associatedwith the detected or selected SSB.

A threshold value of the SSB for the RACH resource association may beset by the network, and RACH preamble is transmitted or retransmitted onthe basis of the SSB in which reference signal received power (RSRP)measured on the basis of the SSB satisfies the threshold value. Forexample, the UE may select one of the SSB (s) satisfying the thresholdvalue and may transmit or retransmit the RACH preamble on the basis ofthe RACH resource associated with the selected SSB.

When a BS receives the random access preamble from the UE, the BStransmits a random access response (RAR) message (Msg2) to the UE. APDCCH that schedules a PDSCH carrying a RAR is CRC masked by a randomaccess (RA) radio network temporary identifier (RNTI) (RA-RNTI) andtransmitted. Upon detection of the PDCCH masked by the RA-RNTI, the UEcan receive a RAR from the PDSCH scheduled by DCI carried by the PDCCH.The UE checks whether the RAR includes random access responseinformation with respect to the preamble transmitted by the UE, that is,Msg1. Presence or absence of random access information with respect toMsg1 transmitted by the UE can be determined according to presence orabsence of a random access preamble ID with respect to the preambletransmitted by the UE. If there is no response to Msg1, the UE canretransmit the RACH preamble less than a predetermined number of timeswhile performing power ramping. The UE calculates PRACH transmissionpower for preamble retransmission on the basis of most recent pathlossand a power ramping counter.

When the random access response information includes timing advanceinformation for UL synchronization and an UL grant, and when a temporaryUE receives a random response information regarding the UE itself on thePDSCH, the UE may know timing advance information for ULsynchronization, an initial UL grant, and a UE temporary cell RNTI (cellRNTI, C-RNTI). The timing advance information is used to control uplinksignal transmission timing. In order to ensure that the PUSCH/PUCCHtransmission by the UE is better aligned with the subframe timing at anetwork end, the network (e.g. BS) may measure a time difference betweenthe PUSCH/PUCCH/SRS reception and subframes and send timing advanceinformation on the basis of the time difference. The UE can perform ULtransmission through Msg3 of the random access procedure over a physicaluplink shared channel on the basis of the random access responseinformation. Msg3 can include an RRC connection request and a UE ID. Thenetwork can transmit Msg4 as a response to Msg3, and Msg4 can be handledas a contention resolution message on DL. The UE can enter an RRCconnected state by receiving Msg4.

Meanwhile, the contention-free random access procedure may be performedwhen the UE performs handover to another cell or BS or when thecontention-free random access procedure is requested by a BS command. Abasic process of the contention-free random access procedure is similarto the contention-based random access procedure. However, unlike thecontention-based random access procedure in which the UE randomlyselects a preamble to be used among a plurality of random accesspreambles, in the case of the contention-free random access procedure, apreamble (hereinafter referred to as a dedicated random access preamble)to be used by the UE is allocated by the BS to the UE. Information onthe dedicated random access preamble may be included in an RRC message(e.g., a handover command) or may be provided to the UE via a PDCCHorder. When the random access procedure is started, the UE transmits adedicated random access preamble to the BS. When the UE receives therandom access procedure from the BS, the random access procedure iscompleted.

As mentioned above, the UL grant in the RAR schedules PUSCH transmissionto the UE. The PUSCH carrying initial UL transmission based on the ULgrant in the RAR will be referred to as Msg3 PUSCH. The content of theRAR UL grant starts at an MSB and ends at a LSB and is given in Table 3.

TABLE 3 RAR UL grant field Number of bits Frequency hopping flag 1 Msg3PUSCH frequency resource allocation 12 Msg3 PUSCH time resourceallocation 4 Modulation and coding scheme (MCS) 4 Transmit power control(TPC) for Msg3 PUSCH 3 CSI request 1

The TPC command is used to determine transmission power of the Msg3PUSCH and is interpreted, for example, according to Table 4.

TABLE 4 TPC command value [dB] 0 −6 1 −4 2 −2 3 0 4 2 5 4 6 6 7 8

In the contention-free random access procedure, the CSI request field inthe RAR UL grant indicates whether the UE includes an aperiodic CSIreport in the corresponding PUSCH transmission. A subcarrier spacing forthe Msg3 PUSCH transmission is provided by an RRC parameter. The UE willtransmit the PRACH and Msg3 PUSCH on the same uplink carrier of the sameservice providing cell. A UL BWP for Msg3 PUSCH transmission isindicated by SIB1 (SystemInformationBlock1).

H. DL and UL Transmitting/Receiving Operations

DL Transmitting/Receiving Operation

A downlink grant (also referred to as a downlink assignment) may bedivided into (1) dynamic grant and (2) configured grant. The dynamicgrant, which is intended to maximize resource utilization, refers to amethod of data transmission/reception on the basis of dynamic schedulingby the BS.

The BS schedules downlink transmission through a DCI. The UE receives onthe PDCCH the DCI for downlink scheduling (i.e., including schedulinginformation of the PDSCH) from the BS. DCI format 1_0 or 1_1 may be usedfor downlink scheduling. The DCI format 1_1 for downlink scheduling mayinclude, for example, the following information: an identifier for DCIformat, a bandwidth part indicator, a frequency domain resourceassignment, time domain resource assignment, MCS.

The UE may determine a modulation order, a target code rate, and atransport block size for the PDSCH on the basis of the MCS field in theDCI. The UE may receive the PDSCH in time-frequency resource accordingto frequency domain resource allocation information and time domainresource allocation information.

The DL grant is also referred to as semi-persistent scheduling (SPS).The UE may receive an RRC message including a resource configuration fortransmission of DL data from the BS. In the case of the DL SPS, anactual DL configured grant is provided by the PDCCH and is activated ordeactivated by the PDCCH. If the DL SPS is configured, at least thefollowing parameters are provided to the UE via RRC signaling from theBS: a configured scheduling RNTI (CS-RNTI) for activation, deactivationand retransmission; and cycle. The actual DL grant of the DL SPS isprovided to the UE by the DCI in the PDCCH addressed to the CS-RNTI. TheUE activates an SPS associated with the CS-RNTI if specific fields ofthe DCI in the PDCCH addressed to the CS-RNTI are set to specific valuesfor scheduling activation. The UE may receive downlink data through thePDSCH on the basis of the SPS.

UL Transmitting/Receiving Operation

The BS transmits a DCI including uplink scheduling information to theUE. The UE receives on the PDCCH the DCI for uplink scheduling (i.e.,including scheduling information of the PUSCH) from the BS. DCI format0_0 or 01 may be used for uplink scheduling. The DCI format 0_1 foruplink scheduling may include the following information: an identifierfor DCI format, a bandwidth part indicator, a frequency domain resourceassignment, a time domain resource assignment, MCS.

The UE transmits uplink data on the PUSCH on the basis of the DCI. Forexample, when the UE detects the PDCCH including the DCI format 0_0 or0_I, the UE transmits the PUSCH according to an instruction based on theDCI. Two transmission schemes are supported for PUSCH transmission:codebook-based transmission and non-codebook-based transmission.

When an RRC parameter ‘txConfig’ receives an RRC message set to‘codebook’, the UE is configured to a codebook-based transmission.Meanwhile, when an RRC message in which the RRC parameter ‘txConfig’ isset to ‘nonCodebook’ is received, the UE is configured to anon-codebook-based transmission. The PUSCH may be semi-staticallyscheduled by the DCI format 0_0, by the DCI format 0_1, or by RRCsignaling.

The uplink grant may be divided into (1) a dynamic grant and (2) aconfigured grant.

FIG. 12 shows an example of an uplink grant. FIG. 12(a) illustrates anUL transmission process based on the dynamic grant, and FIG. 12(b)illustrates an UL transmission process based on the configured grant.

A dynamic grant, which is to maximize utilization of resources, refersto a data transmission/reception method based on dynamic scheduling by aBS. This means that when the UE has data to be transmitted, the UErequests uplink resource allocation from the BS and transmits the datausing only uplink resource allocated by the BS. In order to use theuplink radio resource efficiently, the BS must know how much data eachUE transmits on the uplink. Therefore, the UE may directly transmitinformation on uplink data to be transmitted to the BS, and the BS mayallocate uplink resources to the UE on the basis of the information. Inthis case, the information on the uplink data transmitted from the UE tothe BS is referred to as a buffer status report (BSR), and the BSRrelates to the amount of uplink data stored in a buffer of the UE.

Referring to FIG. 12(a), an uplink resource allocation process foractual data when the UE does not have an uplink radio resource availablefor transmission of the BSR is illustrated. For example, since the UEwhich does not have a UL grant cannot available for UL data transmissioncannot transmit the BSR through a PUSCH, the UE must request resourcefor uplink data must by starting transmission of a scheduling requestvia a PUCCH, and in this case, an uplink resource allocation process offive steps is used.

Referring to FIG. 12(a), if there is no PUSCH resource for transmittinga BSR, the UE first transmits a scheduling request (SR) to the BS inorder to be allocated a PUSCH resource. The SR is used by the UE torequest the BS for PUSCH resources for uplink transmission when areporting event occurs but there is no PUSCH resource available to theUE. Depending on whether there is a valid PUCCH resource for the SR, theUE transmits the SR via the PUCCH or initiates a random accessprocedure. When the UE receives the UL grant from the BS, it transmitsthe BSR to the BS via the PUSCH resource allocated by the UL grant. TheBS checks the amount of data to be transmitted by the UE on the uplinkon the basis of the BSR and transmits a UL grant to the UE. The UEreceiving the UL grant transmits actual uplink data to the BS throughthe PUSCH on the basis of the UL grant.

Referring to FIG. 12(b), the UE receives an RRC message including aresource configuration for transmission of UL data from the BS. Thereare two types of UL-configured grants in the NR system: Type 1 and Type2. In the case of UL-configured grant type 1, an actual UL grant (e.g.,time resource, frequency resource) is provided by RRC signaling, and inthe case of Type 2, an actual UT grant is provided by the PDCCH and isactivated or deactivated by the PDCCH. If the grant type 1 isconfigured, at least the following parameters are provided to the UE viaRRC signaling from the BS: CS-RNTI for retransmission; periodicity ofthe configured grant type 1; information about a start symbol index Sand a symbol length L for an intra-slot PUSCH; time domain offsetrepresenting an offset of the resource for SFN=0 in the time domain; MCSindex indicating modulation order, target code rate, and transport blocksize. If the grant type 2 is configured, at least the followingparameters are provided to the UE via RRC signaling from the BS: CS-RNTIfor activation, deactivation and retransmission; periodicity ofconfigured grant type 2. The actual UL grant of the configured granttype 2 is provided to the UE by the DCI in the PDCCH addressed to theCS-RNTI. If the specific fields of the DCI in the PDCCH addressed to theCS-RNTI are set to a specific value for scheduling activation, the UEactivates the configured grant type 2 associated with the CS-RNTI.

The UE may perform uplink transmission via the PUSCH on the basis of theconfigured grant according to the type 1 or type 2.

Resources for initial transmission by the configured grant may or maynot be shared by one or more UEs.

FIG. 13 shows an example of a conceptual diagram of uplink physicalchannel processing.

Each of the blocks shown in FIG. 13 may be performed in each module inthe physical layer block of a transmission device. More specifically,the uplink signal processing in FIG. 13 may be performed in theprocessor of the UE/BS described in this specification. Referring toFIG. 13, the uplink physical channel processing may be performed throughscrambling, modulation mapping, layer mapping, transform precoding,precoding, resource element mapping, and SC-FDMA signal generation(SC-FDMA signal generation). Each of the above processes may beperformed separately or together in each module of the transmissiondevice. The transform precoding is spreading UL data in a special way toreduce a peak-to-average power ratio (PAPR) of a waveform, and is a kindof discrete Fourier transform (DFT). OFDM using a CP together with thetransform precoding that performs DFT spreading is called DFT-s-OFDM,and OFDM using a CP without DFT spreading is called CP-OFDM. Transformprecoding may optionally be applied if it is enabled for the UL in an NRsystem. That is, the NR system supports two options for UL waveforms,one of which is CP-OFDM and the other is DFT-s-OFDM. Whether the UE mustuse the CP-OFDM as a UL transmit waveform or the DFT-s-OFDM as a ULtransmit waveform is provided from the BS to the UE via RRC parameters.FIG. 13 is a conceptual diagram of uplink physical channel processingfor DFT-s-OFDM. In the case of CP-OFDM, the transform precoding amongthe processes of FIG. 13 is omitted.

More specifically, the transmission device scrambles coded bits in acodeword by a scrambling module, and then transmits the coded bitsthrough a physical channel. Here, the codeword is acquired by encoding atransport block. The scrambled bits are modulated by a modulationmapping module into complex-valued modulation symbols. The modulationmapping module may modulate the scrambled bits according to apredetermined modulation scheme and arrange the modulated bits ascomplex-valued modulation symbols representing a position on a signalconstellation. pi/2-BPSK (pi/2-Binary Phase Shift Keying), m-PSK(m-Phase Shift Keying) or m-QAM (m-Quadrature Amplitude Modulation) maybe used for modulating the coded data. The complex-valued modulationsymbols may be mapped to one or more transport layers by a layer mappingmodule. The complex-valued modulation symbols on each layer may beprecoded by a precoding module for transmission on an antenna port. Ifthe transform precoding is enabled, the precoding module may performprecoding after performing transform precoding on the complex-valuedmodulation symbols as shown in FIG. 13. The precoding module may processthe complex-valued modulation symbols in a MIMO manner according tomultiple transmission antennas to output antenna-specific symbols, anddistribute the antenna-specific symbols to a corresponding resourceelement mapping module. An output z of the precoding module may beacquired by multiplying an output y of the layer mapping module by aprecoding matrix W of N×M. Here, N is the number of antenna ports and Mis the number of layers. The resource element mapping module maps thecomplex-valued modulation symbols for each antenna port to anappropriate resource element in the resource block allocated fortransmission. The resource element mapping module may map thecomplex-valued modulation symbols to appropriate subcarriers andmultiplex the same according to users. The SC-FDMA signal generationmodule (CP-OFDM signal generation module if the transform precoding isdisabled) modulates the complex-valued modulation symbol according to aspecific modulation scheme, for example, an OFDM scheme, to generate acomplex-valued time domain OFDM (Orthogonal Frequency DivisionMultiplexing) symbol signal. The signal generation module may performInverse Fast Fourier Transform (IFFT) on the antenna specific symbol,and a CP may be inserted into the time domain symbol on which the IFFThas been performed. The OFDM symbol undergoes digital-to-analogconversion, upconverting, and the like, and transmitted to a receptiondevice through each transmission antenna. The signal generation modulemay include an IFFT module and a CP inserter, a digital-to-analogconverter (DAC), and a frequency uplink converter.

A signal processing procedure of a reception device may be the reverseof the signal processing procedure of the transmission device. Detailsthereof may be referred to the above contents and FIG. 13.

Next, the PUCCH will be described.

The PUCCH supports a plurality of formats, and the PUCCH formats may beclassified according to symbol duration, payload size, multiplexing, andthe like. Table 5 below illustrates PUCCH formats.

TABLE 5 PUCCH length in OFDM Number Format symbols of bits Usage Etc. 01-2  ≤2 1 Sequence selection 1 4-14 ≤2 2 Sequence modulation 2 1-2  >2 4CP-OFDM 3 4-14 >2 8 DFT-s-OFDM(no UE multiplexing) 4 4-14 >2 16DFT-s-OFDM(Pre DFT orthogonal cover code(OCC))

The PUCCH formats shown in Table 5 may be divided into (1) a short PUCCHand (2) a long PUCCH. PUCCH formats 0 and 2 may be included in the shortPUCCH, and PUCCH formats 1, 3 and 4 may be included in the long PUCCH.

FIG. 14 shows an example of an NR slot in which a PUCCH is transmitted.

The UE transmits one or two PUCCHs through serving cells in differentsymbols in one slot. When the UE transmits two PUCCHs in one slot, atleast one of the two PUCCHs has a structure of the short PUCCH.

I. eMBB (Enhanced Mobile Broadband Communication)

In the case of the NR system, a massive multiple input multiple output(MIMO) environment in which the transmit/receive antennas aresignificantly increased may be considered. That is, as the large MIMOenvironment is considered, the number of transmit/receive antennas mayincrease to several tens or hundreds or more. Meanwhile, the NR systemsupports communication in above 6 GHz band, that is, the millimeterfrequency band. However, the millimeter frequency band has a frequencycharacteristic in which signal attenuation according to a distance isvery sharp due to the use of a frequency band which is too high.Therefore, an NR system using the band of 6 GHz or higher uses abeamforming technique in which energy is collected and transmitted in aspecific direction, not in all directions, in order to compensate forsudden propagation attenuation characteristics. In the massive MIMOenvironment, a hybrid type beamforming technique combining an analogbeamforming technique and a digital beamforming technique is requireddepending on a position to which a beamforming weight vector/precodingvector is applied, to reduce complexity of hardware implementation,increase performance using multiple antennas, obtain flexibility ofresource allocation, and facilitate beam control for each frequency.

Hybrid Beamforming

FIG. 15 illustrates an example of a block diagram of a transmitter and areceiver for hybrid beamforming.

As a method for forming a narrow beam in a millimeter frequency band, abeam forming scheme in which energy is increased only in a specificdirection by transmitting the same signal using a phase differencesuitable for a large number of antennas in a BS or a UE is mainlyconsidered. Such beamforming scheme includes digital beamforming tocreate a phase difference in a digital baseband signal, analogbeamforming to create a phase difference in a modulated analog signalusing time delay (i.e., cyclic shift), and hybrid beamforming using bothdigital beamforming and analog beamforming, or the like. If each antennaelement has an RF unit (or transceiver unit (TXRU)) to adjusttransmission power and phase, independent beamforming is possible foreach frequency resource. However, it is not effective in terms of priceto install an RF unit in all 100 antenna elements. That is, since themillimeter frequency band requires a large number of antennas tocompensate for the sudden attenuation characteristics and digitalbeamforming requires an RF component (e.g., a digital-to-analogconverter (DAC), a mixer, a power amplifier, a linear amplifier, and thelike), implementation of digital beamforming in the millimeter frequencyband causes the price of the communication device to increase.Therefore, when a large number of antennas are required such as in themillimeter frequency band, the use of analog beamforming or hybridbeamforming is considered. In the analog beamforming scheme, a pluralityof antenna elements are mapped to one TXRU and a direction of a beam isadjusted by an analog phase shifter. Such an analog beamforming schememay generate only one beam direction in the entire band, and thus, itcannot perform frequency selective beamforming (BF). Hybrid BF is anintermediate form of digital BF and analog BF and has B RF units fewerthan Q antenna elements. In the case of the hybrid BF, directions ofbeams that may be transmitted at the same time is limited to B or less,although there is a difference depending on a method of connecting the BRF units and Q antenna elements.

Beam Management (BM)

The BM process includes processes for acquiring and maintaining a set ofBS (or a transmission and reception point (TRP)) and/or UE beams thatmay be used for downlink (DL) and uplink (UL) transmission/reception andmay include the following processes and terms.

-   -   beam measurement: operation for BS or UE to measure        characteristic of received beamforming signal.    -   beam determination: operation for BS or UE to select its own Tx        beam/Rx beam.    -   beam sweeping: an operation to cover spatial domain using        transmission and/or reception beam during a predetermined time        interval in a predetermined manner.    -   beam report: an operation for UE to report information of        beamformed signal on the basis of beam measurement.

The BM process may be classified into (1) DL BM process using SSB orCSI-RS and (2) UL BM process using SRS (sounding reference signal).Also, each BM process may include Tx beam sweeping to determine Tx beamand Rx beam sweeping to determine Rx beam.

DL BM Process

The DL BM process may include (1) transmission of beamformed DL RSs(e.g., CSI-RS or SSB) by the BS, and (2) beam reporting by the UE.

Here, the beam report may include a preferred DL RS ID(s) and acorresponding reference signal received power (RSRP). The DL RS ID maybe an SSBRI (SSB Resource Indicator) or a CRI (CSI-RS ResourceIndicator).

FIG. 16 shows an example of beamforming using SSB and CSI-RS.

As shown in FIG. 16, the SSB beam and the CSI-RS beam may be used forbeam measurement. The measurement metric is an RSRP per resource/block.The SSB may be used for coarse beam measurement, and the CSI-RS may beused for fine beam measurement. SSB may be used for both Tx beamsweeping and Rx beam sweeping. Rx beam sweeping using the SSB may beperformed by attempting to receive the SSB while the UE changes the Rxbeam for the same SSBRI across multiple SSB bursts. Here, one SS burstmay include one or more SSBs, and one SS burst set includes one or moreSSB bursts.

1. DL BM Using SSB

FIG. 17 is a flowchart illustrating an example of a DL BM process usingSSB.

A configuration for beam report using the SSB is performed at the timeof channel state information (CSI)/beam configuration in RRC_CONNECTED.

-   -   The UE receives from the BS a CSI-ResourceConfig IE including a        CSI-SSB-ResourceSetList for the SSB resources used for the BM        (S410). The RRC parameter csi-SSB-ResourceSetList represents a        list of SSB resources used for beam management and reporting in        one resource set. Here, the SSB resource set may be configured        to {SSBx1, SSBx2, SSBx3, SSBx4}. The SSB index may be defined        from 0 to 63.    -   The UE receives signals on the SSB resources from the BS on the        basis of the CSI-SSB-ResourceSetList (S420).    -   If the CSI-RS reportConfig associated with reporting on the        SSBRI and reference signal received power (RSRP) is configured,        the UE reports the best SSBRI and its corresponding RSRP to the        BS S430). For example, if the reportQuantity of the CSI-RS        reportConfig IE is set to ‘ssb-Index-RSRP’, the UE reports the        best SSBRI and a corresponding RSRP to the BS.

When the CSI-RS resource is configured in the same OFDM symbol (s) asthe SSB and ‘QCL-Type D’ is applicable, the UE may assume that theCSI-RS and the SSB are quasi co-located (QCL-ed) in terms of‘QCL-TypeD’. Here, QCL-TypeD may refer to QCL-ed between antenna portsin terms of spatial Rx parameter. The same receive beam may be appliedwhen the UE receives signals of a plurality of DL antenna ports in theQCL-TypeD relationship. Details of QCL may refer to a section 4. QCLbelow.

2. DL BM Using CSI-RS

Referring to the use of CSI-RS, i) if a repetition parameter is set fora specific CSI-RS resource set and TRS_info is not configured, CSI-RS isused for beam management. ii) If the repetition parameter is not set andTRS_info is set, the CSI-RS is used for a tracking reference signal(TRS). Iii) If the repetition parameter is not set and TRS_info is notset, the CSI-RS is used for CSI acquisition.

(RRC Parameter) If the repetition is set to ‘ON’, it relates to a Rxbeam sweeping process of the UE. If the repetition is set to ‘ON’, theUE may assume that if NZP-CSI-RS-ResourceSet is configured, signals ofat least one CSI-RS resource in the NZP-CSI-RS-ResourceSet aretransmitted in the same downlink space domain filter. That is, at leastone CSI-RS resource in the NZP-CSI-RS-ResourceSet is transmitted throughthe same Tx beam. Here, signals of at least one CSI-RS resource in theNZP-CSI-RS-ResourceSet may be transmitted in different OFDM symbols.

Meanwhile, if the repetition is set to ‘OFF’, it relates to a Tx beamsweeping process of the BS. If the repetition is set to ‘OFF’, the UEdoes not assume that signals of at least one CSI-RS resource in theNZP-CSI-RS-ResourceSet are transmitted in the same downlink spatialdomain transmission filter. That is, the signals of at least one CSI-RSresource in the NZP-CSI-RS-ResourceSet are transmitted through differentTx beams. FIG. 18 shows another example of the DL BM process usingCSI-RS.

FIG. 18(a) shows a process of Rx beam determination (or refinement) ofthe UE, and FIG. 18(b) shows a Tx beam sweeping process of the BS. FIG.18 (a) shows a case where the repetition parameter is set to ‘ON’, andFIG. 18(b) shows a case where the repetition parameter is set to ‘OFF’.

A process of determining the Rx beam of the UE will be described withreference to FIGS. 18(a) and 19.

FIG. 19 is a flowchart illustrating an example of a process ofdetermining a reception beam of a UE.

-   -   The UE receives an NZP CSI-RS resource set IE including the RRC        parameter regarding ‘repetition’ from the BS through RRC        signaling (S610). Here, the RRC parameter ‘repetition’ is set to        ‘ON’.    -   The UE repeatedly receives signals on the resource(s) in the        CSI-RS resource in which the RRC parameter ‘repetition’ is set        to ‘ON’ in different OFDM (s) through the same Tx beam (or DL        space domain transmission filter) of the BS (S620).    -   The UE determines its own Rx beam (S630).    -   The UE omits the CSI reporting (S640). That is, the UE may omit        CSI reporting when the uplink RRC parameter ‘repetition’ is set        to ‘ON’.

A Tx beam determining process of the BS will be described with referenceto FIGS. 18(b) and 20.

FIG. 20 is a flowchart illustrating an example of a transmission beamdetermining process of the BS.

-   -   The UE receives an NZP CSI-RS resource set IE including an RRC        parameter regarding ‘repetition’ from the BS through RRC        signaling (S710). Here, the RRC parameter ‘repetition’ is set to        ‘OFF’ and is related to the Tx beam sweeping process of the BS.    -   The UE receives signals on the resources in the CSI-RS resource        in which the RRC parameter ‘repetition’ is set to ‘OFF’ through        different Tx beams (DL spatial domain transmission filters) of        the BS (S720).    -   The UE selects (or determines) the best beam (S730)    -   The UE reports an ID (e.g., CRI) for the selected beam and        related quality information (e.g., RSRP) to the BS (S740). That        is, the UE reports the CRI and the RSRP to the BS when the        CSI-RS is transmitted for the BM.

FIG. 21 shows an example of resource allocation in time and frequencydomains related to the operation of FIG. 18.

When repetition ‘ON’ is set in the CSI-RS resource set, a plurality ofCSI-RS resources are repeatedly used by applying the same transmissionbeam, and when repetition ‘OFF’ is set in the CSI-RS resource set,different CSI-RS resources may be transmitted in different transmissionbeams.

3. DL BM-Related Beam Indication

The UE may receive a list of up to M candidate transmissionconfiguration indication (TCI) states for at least a quasi co-location(QCL) indication via RRC signaling. Here, M depends on UE capability andmay be 64.

Each TCI state may be configured with one reference signal (RS) set.Table 6 shows an example of a TCI-State IE. The TCI-State IE isassociated with a quasi co-location (QCL) type corresponding to one ortwo DL reference signals (RSs).

TABLE 6 -- ASN1START -- TAG-TCI-STATE-START TCI-State ::= SEQUENCE {tci-StateId TCI-StateId, qcl-Type1 QCL-Info, qcl-Type2 QCL-InfoOPTIONAL, -- Need R ... } QCL-Info ::= SEQUENCE { cell ServCellIndexOPTIONAL, -- Need R bwp-Id BWP-Id OPTIONAL, -- Cond CSI-RS-IndicatedreferenceSignal CHOICE { csi-rs NZP-CSI-RS-ResourceId, ssb SSB-Index },qcl-Type ENUMERATED {typeA, typeB, typeC, typeD}, ... } --TAG-TCI-STATE-STOP -- ASN1STOP

In Table 6, ‘bwp-Id’ denotes a DL BWP where RS is located, ‘cell’denotes a carrier where RS is located, ‘referencesignal’ denotes areference antenna port(s) which is a QCL-ed source for target antennaport(s) or a reference signal including the same. The target antennaport(s) may be CSI-RS, PDCCH DMRS, or PDSCH DMRS.

4. QCL (Quasi-Co Location)

The UE may receive a list including up to M TCI-state configurations todecode the PDSCH according to the detected PDCCH having an intended DCIfor the UE and a given cell. Here, M depends on the UE capability.

As illustrated in Table 6, each TCI-State includes a parameter forestablishing a QCL relationship between one or two DL RSs and the DM-RSport of the PDSCH. The QCL relationship is configured with a RRCparameter qcl-Type1 for the first DL RS and a qcl-Type2 (if set) for thesecond DL RS.

The QCL type corresponding to each DL RS is given by the parameter‘qcl-Type’ in QCL-Info and may have one of the following values:

-   -   ‘QCL-TypeA’: {Doppler shift, Doppler spread, average delay,        delay spread}    -   ‘QCL-TypeB’: {Doppler shift, Doppler spread}    -   ‘QCL-TypeC’: {Doppler shift, average delay}    -   ‘QCL-TypeD’: {Spatial Rx parameter}

For example, when a target antenna port is a specific NZP CSI-RS,corresponding NZP CSI-RS antenna ports may be instructed/configured tobe QCL-ed with a specific TRS in terms of QCL-Type A and QCL-ed with aspecific SSB in terms of QCL-Type D. The thusly instructed/configured UEmay receive the corresponding NZP CSI-RS using a Doppler and delay valuemeasured by the QCL-TypeA TRS and apply a reception beam used forreceiving the QCL-TypeD SSB to the corresponding NZP CSI-RS reception.

UL BM Process

In the UL BM, a Tx beam-Rx beam reciprocity (or beam correspondence) maybe or may not be established depending on UE implementation. If the Txbeam-Rx beam reciprocity is established in both the BS and the UE, a ULbeam pair may be matched through a DL beam pair. However, if the Txbeam-Rx beam reciprocity is not established in either the BS or the UE,a UL beam pair determining process is required, apart from DL beam pairdetermination.

In addition, even when the BS and the UE maintain beam correspondence,the BS may use the UL BM process for DL Tx beam determination withoutrequesting the UE to report a preferred beam.

The UL BM may be performed through beamformed UL SRS transmission andwhether to apply the UL BM of the SRS resource set is configured by theRRC parameter in a (RRC parameter) usage. If the usage is configured as‘BeamManagement (BM)’, only one SRS resource may be transmitted for eachof a plurality of SRS resource sets at a given time instant.

The UE may be configured with one or more sounding reference signal(SRS) resource sets (through RRC signaling, etc.) set by the (RRCparameter) SRS-ResourceSet. For each SRS resource set, K≥1 SRS resourcesmay be set for the UE. Here, K is a natural number, and a maximum valueof K is indicated by SRS_capability.

Like the DL BM, the UL BM process may also be divided into Tx beamsweeping of the UE and Rx beam sweeping of the BS.

FIG. 22 shows an example of a UL BM process using SRS.

FIG. 22(a) shows a process of determining Rx beamforming of a BS, andFIG. 22(b) shows a process of sweeping Tx beam of the UE.

FIG. 23 is a flowchart illustrating an example of a UL BM process usingSRS.

-   -   The UE receives RRC signaling (e.g., SRS-Config IE) including an        (RRC parameter) usage parameter set to ‘beam management’ from        the BS (S1010). An SRS-Config IE is used for configuration of        SRS transmission. The SRS-Config IE includes a list of        SRS-Resources and a list of SRS-ResourceSets. Each SRS resource        set refers to a set of SRS-resources.    -   The UE determines Tx beamforming for the SRS resource to be        transmitted on the basis of SRS-SpatialRelation Info included in        the SRS-Config IE (S1020). Here, the SRS-SpatialRelation Info is        configured for each SRS resource and indicates whether to apply        the same beamforming as that used in SSB, CSI-RS, or SRS for        each SRS resource.    -   If SRS-SpatialRelationInfo is configured in the SRS resource,        the same beamforming as that used in SSB, CSI-RS, or SRS is        applied and transmitted. However, if SRS-SpatialRelationInfo is        not configured in the SRS resource, the UE randomly determines        the Tx beamforming and transmits the SRS through the determined        Tx beamforming (S1030).

More specifically, regarding P-SRS in which ‘SRS-ResourceConfigType’ isset to ‘periodic’:

i) If the SRS-SpatialRelationInfo is set to ‘SSB/PBCH’, the UE transmitsthe corresponding SRS by applying the same spatial domain transmissionfilter (or generated from the corresponding filter) as the spatialdomain Rx filter used for receiving SSB/PBCH; or

ii) If the SRS-SpatialRelationInfo is set to ‘CSI-RS’, the UE transmitsthe SRS by applying the same spatial domain transmission filter used forreceiving the CSI-RS; or

iii) When SRS-SpatialRelationInfo is set to ‘SRS’, the UE transmits thecorresponding SRS by applying the same spatial domain transmissionfilter used for transmitting the SRS.

-   -   In addition, the UE may receive or may not receive a feedback on        the SRS from the BS as in the following three cases (S1040).

i) When Spatial_Relation_Info is set for all SRS resources in the SRSresource set, the UE transmits the SRS to the beam indicated by the BS.For example, if Spatial_Relation_Info indicates SSB, CRI, or SRI inwhich Spatial_Relation_Info is the same, the UE repeatedly transmits theSRS on the same beam.

ii) Spatial_Relation_Info may not be set for all SRS resources in theSRS resource set. In this case, the UE may freely transmit whilechanging the SRS beamforming.

iii) Spatial_Relation_Info may only be set for some SRS resources in theSRS resource set. In this case, the SRS is transmitted on the indicatedbeam for the set SRS resource, and for an SRS resource in whichSpatial_Relation_Info is not set, the UE may transit the SRS resource byrandomly applying Tx beamforming.

A Beam Failure Recovery (BFR) Process

In a beamformed system, a radio link failure (RLF) may occur frequentlydue to rotation, movement, or beamforming blockage of the UE. Therefore,BFR is supported in NR to prevent frequent occurrence of the RLFs. TheBFR is similar to the radio link failure recovery process and may besupported if the UE knows the new candidate beam(s).

For beam failure detection, the BS configures beam failure detectionreference signals for the UE, and if the number of times of beam failureindications from the physical layer of the UE reaches a threshold set bythe RRC signaling within a period set by the RRC signaling of the BS,the UE declares beam failure.

After the beam failure is detected, the UE triggers a beam failurerecovery by initiating a random access procedure on the PCell; andperforms beam failure recovery by selecting a suitable beam (If the BSprovides dedicated random access resources for certain beams, they areprioritized by the UE). Upon completion of the random access procedure,beam failure recovery is considered to be completed.

J. URLLC (Ultra-Reliable and Low Latency Communication)

The URLLC transmission defined by the NR may refer to transmission for(1) a relatively low traffic size, (2) a relatively low arrival rate,(3) an extremely low latency requirement (e.g., 0.5, 1 ms), (4)relatively short transmission duration (e.g., 2 OFDM symbols), and (5)urgent service/message, etc.

In the case of UL, transmission for a particular type of traffic (e.g.,URLLC) needs to be multiplexed with other previously scheduledtransmissions (e.g., eMBB) to meet a more stringent latency requirement.In this regard, one method is to give information indicating that ascheduled UE will be preempted for a specific resource, and allow theURLLC UE to use the resource for UL transmission.

Pre-Emption Indication

In the case of NR, dynamic resource sharing between eMBB and URLLC issupported. eMBB and URLLC services may be scheduled on non-overlappingtime/frequency resources and URLLC transmission may occur on scheduledresources for ongoing eMBB traffic. The eMBB UE may not know whetherPDSCH transmission of the UE is partially punctured and the UE may notbe able to decode the PDSCH due to corrupted coded bits. Inconsideration of this, NR provides a preemption indication.

The preemption indication may also be referred to as an interruptedtransmission indication.

With respect to the preamble indication, the UE receivesDownlinkPreemption IE through RRC signaling from the BS. Table 7 belowshows an example of the DownlinkPreemption IE.

TABLE 7 -- ASN1START -- TAG-DOWNLINKPREEMPTION-START DownlinkPreemption::= SEQUENCE { int-RNTI RNTI-Value, timeFrequencySet  ENUMERATED {set0,set1}, dci-PayloadSize INTEGER (0..maxINT-DCI-PayloadSize),int-ConfigurationPerServingCell SEQUENCE (SIZE (1..maxNrofServingCells))OF INT-ConfigurationPerServingCell,  ... }INT-ConfigurationPerServingCell ::= SEQUENCE { servingCellIdServCellIndex, positionInDCI  INTEGER (0..maxINT-DCI-PayloadSize−1) } --TAG-DOWNLINKPREEMPTION-STOP -- ASN1STOP

If the UE is provided with the DownlinkPreemption IE, the UE isconfigured with an INT-RNTI provided by a parameter int-RNTI in theDownlinkPreemption IE to monitor a PDCCH conveying the DCI format 2_1.The UE is further configured with a set of serving cells and acorresponding set of locations for fields in the DCI format 2_1 bypositionInDCI by an INT-ConfigurationPerServing Cell including a set ofserving cell indices provided by a servingCellID, is configured with aninformation payload size for DCI format 2_1 by dci-PayloadSize, and isconfigured with granularity of time-frequency resources bytimeFrequencySect.

The UE receives the DCI format 2_1 from the BS on the basis of theDownlinkPreemption IE.

If the UE detects the DCI format 2_1 for a serving cell in the set ofserving cells, the UE may assume there is no transmission to the UE inPRBs and symbols indicated by the DCI format 2_1 among sets of PRBs andsets of symbols in the last monitoring period before a monitoring periodto which the DCI format 2_1 belongs. For example, referring to FIG. 9A,the UE determines that a signal in the time-frequency resource indicatedby pre-emption is not a DL transmission scheduled for the UE itself anddecodes data on the basis of signals received in the remaining resourcearea.

FIG. 24 is a diagram showing an example of an preemption indicationmethod.

A combination of {M,N} is set by the RRC parameter timeFrequencySet. {M,N}={14,1}, {7,2}.

FIG. 25 shows an example of a time/frequency set of a preemptionindication.

A 14-bit bitmap for a preemption indication indicates one or morefrequency parts (N>=1) and/or one or more time domain parts (M>=1). Inthe case of {M, N}={14,1}, as shown in FIG. 25(a), 14 parts in the timedomain correspond one-to-one to 14 bits of the 14-bit bit map, and apart corresponding to a bit set to 1, among the 14 bits, is partincluding preempted resources. In the case of {M, N}={7,2}, as shown inFIG. 25(b), the time-frequency resources of the monitoring period isdivided into seven parts in the time domain and two parts in thefrequency domain, so as to be divided into a total of 14 time-frequencyparts. The total of 14 time-frequency parts correspond one-to-one to the14 bits of the 14-bit bitmap, and the part corresponding to the bit setto 1 among the 14 bits includes the pre-empted resources.

K. MMTC (Massive MTC)

The massive machine type communication (mMTC) is one of the 5G scenariosfor supporting a hyper-connection service that simultaneouslycommunicates with a large number of UEs. In this environment, the UEintermittently performs communication with a very low transfer rate andmobility. Therefore, mMTC is aimed at how low cost and for how long theUE can be driven. In this regard, MTC and NB-IoT, which are dealt within 3GPP will be described.

Hereinafter, a case where a transmission time interval of a physicalchannel is a subframe will be described as an example. For example, acase where a minimum time interval from a start of transmission of onephysical channel (e.g., MPDCCH, PDSCH, PUCCH, PUSCH) to a start oftransmission of a next physical channel is one subframe will bedescribed as an example. In the following description, the subframe maybe replaced by a slot, a mini-slot, or multiple slots.

MTC (Machine Type Communication)

MTC (Machine Type Communication), which is an application that does notrequire much throughput applicable to M2M (Machine-to-Machine) or IoT(Internet-of-Things), refers to a communication technology adopted tomeet the requirements of the IoT service in 3GPP (3rd GenerationPartnership Project).

The MTC may be implemented to meet the criteria of (1) low cost & lowcomplexity, (2) enhanced coverage, and (3) low power consumption.

In 3GPP, MTC has been applied since release 10 (3GPP standard documentversion 10.x.x.) and features of MTC added for each release of 3GPP willbe briefly described.

First, the MTC described in 3GPP Release 10 and Release 11 relates to aload control method. The load control method is to prevent IoT (or M2M)devices from suddenly loading the BS. More specifically, 3GPP Release 10relates to a method of controlling a load by disconnecting IoT deviceswhen the load occurs, and Release 11 relates to a method of preventingconnection of the UE in advance by informing the UE about connection toa cell later through system information of the cell. In Release 12,features for low cost MTC are added, for which UE category 0 is newlydefined. The UE category is an indicator indicating how much data the UEmay handle at a communication modem. A UE in UE category 0 is a UE witha reduced peak data rate and relaxed radio frequency (RF) requirements,thus reducing baseband and RF complexity. In Release 13, a technologycalled eMTC (enhanced MTC) was introduced, which allows the UE tooperate only at 1.08 MHz, a minimum frequency bandwidth supported bylegacy LTE, thereby lowering the price and power consumption of the UE.

The contents described hereinafter is features mainly related to eMTCbut may also be equally applicable to the MTC, eMTC, 5G (or NR) unlessotherwise mentioned. Hereinafter, for convenience of explanation, MTCwill be collectively described.

Therefore, the MTC described below may referred to as the enhanced MTC(eMTC), the LTE-M1/M2, BL (bandwidth reduced low complexity/CE (coverageenhanced), non-BL UE (in enhanced coverage), NR MTC, enhanced BL/CE, andthe like. That is, the term MTC may be replaced with terms to be definedin the 3GPP standard in the future.

MTC General Features

(1) MTC operates only within a specific system bandwidth (or channelbandwidth).

MTC may use six resource blocks (RBs) in the system band of the legacyLTE as shown in FIG. 26 or use a specific number of RBs in the systemband of the NR system. The frequency bandwidth in which the MTC operatesmay be defined in consideration of a frequency range of NR andsubcarrier spacing. Hereinafter, a specific system or frequencybandwidth in which the MTC operates is referred to as an MTC narrowband(NB). In the NR, the MTC may operate in at least one bandwidth part(BWP) or in a specific band of BWP.

MTC follows a narrowband operation to transmit and receive physicalchannels and signals, and a maximum channel bandwidth in which the MTCUE is operable is reduced to 1.08 MHz or six (LTE) RBs.

The narrowband may be used as a reference unit in resource allocationunits of some downlink and uplink channels, and a physical location ofeach narrowband in the frequency domain may be defined to be differentdepending on the system bandwidth.

The bandwidth of 1.08 MHz defined in MTC is defined for the MTC UE tofollow the same cell search and random access procedure as the legacyUE.

MTC may be supported by cells having a bandwidth (e.g., 10 MHz) muchlarger than 1.08 MHz but the physical channels and signals transmittedand received by the MTC are always limited to 1.08 MHz. The system withhaving much larger bandwidth may be legacy LTE, NR systems, 5G systems,and the like.

A narrowband is defined as six non-overlapping consecutive physicalresource blocks in the frequency domain.

FIG. 26(a) is a diagram showing an example of a narrowband operation,and FIG. 26(b) is a diagram showing an example of repetition having RFretuning.

Frequency diversity by RF retuning will be described with reference toFIG. 26(b).

Due to narrowband RF, single antenna and limited mobility, the MTCsupports limited frequency, space and time diversity. In order to reducefading and outage, frequency hopping is supported by MTC betweendifferent narrow bands by RF retuning.

In MTC, frequency hopping is applied to different uplink and downlinkphysical channels when repetition is possible. For example, if 32subframes are used for PDSCH transmission, first 16 subframes may betransmitted on a first narrowband. Here, the RF front end is retuned toanother narrow band, and the remaining 16 subframes are transmitted onthe second narrow band.

The narrowband of MTC may be set to the UE via system information or DCI(downlink control information) transmitted by the BS.

(2) The MTC operates in a half duplex mode and uses a limited (orreduced) maximum transmit power. The half duplex mode refers to a modein which a communication device operates only in an uplink or a downlinkat one frequency at one time point and operates in a downlink or anuplink at another frequency at another time point. For example, when thecommunication device operates in the half-duplex mode, the communicationdevice performs communication using the uplink frequency and thedownlink frequency, and the communication device may not use the uplinkfrequency and the downlink frequency at the same time. The communicationdevice divides time to perform uplink transmission through the uplinkfrequency and the downlink reception by re-tuning to the downlinkfrequency for another predetermined time.

(3) MTC does not use channels (defined in legacy LTE or NR) that must bedistributed over the entire system bandwidth of the legacy LTE or NR.For example, in the MTC, the PDCCH of the legacy LTE is not used becausethe PDCCH is distributed over the entire system bandwidth. Instead, anew control channel, MPDCCH (MTC PDCCH), is defined in the MTC. TheMPDCCH is transmitted/received within a maximum of 6 RBs in thefrequency domain.

(4) MTC uses the newly defined DCI format. For example, DCI formats6-0A, 6-0B, 6-1A, 6-1B, 6-2, etc., may be used as a DCI format for MTC(see 3GPP TS 36.212).

(5) In the case of MTC, a physical broadcast channel (PBCH), a physicalrandom access channel (PRACH), an MTC physical downlink control channel(M-PDCCH), a physical downlink shared channel (PDSCH), a physical uplinkcontrol channel (PUCCH), and a physical uplink shared channel (PUSCH)may be repeatedly transmitted. Due to the MTC repeated transmission, anMTC channel may be decoded even when signal quality or power is verypoor, such as in an inadequate environment such as a basement, therebyincreasing a cell radius and increasing a penetration effect.

(6) In MTC, PDSCH transmission based on PDSCH scheduling (DCI) and PDSCHscheduling may occur in different subframes (cross-subframe scheduling).

(7) In the LTE system, the PDSCH carrying a general SIB1 is scheduled bythe PDCCH, whereas all the resource allocation information (e.g.,subframe, transport block size, narrowband index) for SIB1 decoding isdetermined by a parameter of the MIB and no control channel is used forSIB1 decoding of the MTC.

(8) All resource allocation information (subframe, TBS, subband index)for SIB2 decoding is determined by several SIB1 parameters and nocontrol channel for SIB2 decoding of MTC is used.

(9) The MTC supports an extended paging (DRX) cycle. Here, the pagingperiod refers to a period during which the UE must be wake up to checkwhether there is a paging from a network even when the UE is in adiscontinuous reception (DRX) mode in which it does not attempt toreceive a downlink signal for power saving.

(10) MTC may use the same PSS (Primary Synchronization Signal)/SSS(Secondary Synchronization Signal)/CRS (Common Reference Signal) used inlegacy LTE or NR. In the case of NR, the PSS/SSS is transmitted on anSSB basis, and a tracking RS (TRS) is a cell-specific RS and may be usedfor frequency/time tracking.

MTC Operation Mode and Level

Next, an MTC operation mode and level will be described. MTC isclassified into two operation modes (first mode, second mode) and fourdifferent levels for coverage improvement as shown in Table 8 below.

The MTC operation mode is referred to as a CE (Coverage Enhancement)mode. In this case, the first mode may be referred to as a CE mode A,and the second mode may be referred to as a CE mode B.

TABLE 8 Mode Level Description Mode A Level 1 No repetition for PRACHLevel 2 Small Number of Repetition for PRACH Mode B Level 3 MediumNumber of Repetition for PRACH Level 4 Large Number of Repetition forPRACH

The first mode is defined for small coverage enhancement to support fullmobility and CSI (channel state information, in which there is norepetition or fewer repetition times. The second mode is defined for UEswith extremely poor coverage conditions that support CSI feedback andlimited mobility, in which a large number of repetitive transmissions isdefined. The second mode provides a coverage improvement of up to 15 dB.Each level of MTC is defined differently in the random access procedureand the paging process.

The MTC operation mode is determined by the BS, and each level isdetermined by the MTC UE. Specifically, the BS transmits RRC signalingincluding information on the MTC operation mode to the UE. Here, the RRCsignaling may be an RRC connection setup message, an RRC connectionreconfiguration message or an RRC connection reestablishment message.

Thereafter, the MTC UE determines a level in each operation mode andtransmits the determined level to the BS. Specifically, the MTC UEdetermines a level in an operation mode on the basis of measured channelquality (e.g., reference signal received power (RSRP), reference signalreceived quality (RSRQ), or signal to interference plus noise ratio(SINR), and transmits an RACH preamble using a PRACH resource (e.g.,frequency, time, preamble resource for PRACH) corresponding to thedetermined level, thereby informing the BS about the determined level.

MTC Guard Period

As discussed above, MTC operates in narrow band. The location of thenarrow band used in the MTC may be different for each particular timeunit (e.g., subframe or slot). The MTC UE may tune to differentfrequencies depending on the time units. A certain amount of time isrequired for frequency retuning, and certain amount of time is definedas a guard period of MTC. That is, a guard period is required whenfrequency retuning is performed while transitioning from one time unitto the next time unit, and transmission and reception do not occurduring the guard period.

MTC Signal Transmission/Reception Method

FIG. 27 is a diagram illustrating physical channels that may be used forMTC and a general signal transmission method using the same.

In step S1001, the MTC UE, which is powered on again or enters a newcell, performs an initial cell search operation such as synchronizingwith the BS. To this end, the MTC UE receives a primary synchronizationsignal (PSS) and a secondary synchronization signal (SSS) from the BS,adjusts synchronization with the BS, and acquires information such as acell ID. The PSS/SSS used in the initial cell search operation of theMTC may be a PSS/SSS, a resynchronization signal (RSS), or the like ofan legacy LTE.

Thereafter, the MTC UE may receive a physical broadcast channel (PBCH)signal from the BS to acquire broadcast information in a cell.

Meanwhile, the MTC UE may receive a downlink reference signal (DL RS) inan initial cell search step to check a downlink channel state. Thebroadcast information transmitted through the PBCH is a masterinformation block (MIB), and in the LTE, the MIB is repeated by every 10ms.

Among the bits of the MIB of the legacy LTE, reserved bits are used inMTC to transmit scheduling for a new SIB1-BR (system information blockfor bandwidth reduced device) including a time/frequency location and atransport block size. The SIB-BR is transmitted directly on the PDSCHwithout any control channel (e.g., PDCCH, MPDDCH) associated with theSIB-BR.

Upon completion of the initial cell search, the MTC UE may receive anMPDCCH and a PDSCH according to the MPDCCH information to acquire morespecific system information in step S1002. The MPDCCH may be transmittedonly once or repeatedly. The maximum number of repetitions of the MPDCCHis set to the UE by RRC signaling from the BS.

Thereafter, the MTC UE may perform a random access procedure such assteps S1003 to S1006 to complete the connection to the BS. A basicconfiguration related to the RACH process of the MTC UE is transmittedby SIB2. In addition, SIB2 includes parameters related to paging. In the3GPP system, a paging occasion (PO) refers to a time unit in which theUE may attempt to receive paging. The MTC UE attempts to receive theMPDCCH on the basis of a P-RNTI in the time unit corresponding to its POon the narrowband (PNB) set for paging. The UE that has successfullydecoded the MPDCCH on the basis of the P-RNTI may receive a PDSCHscheduled by the MPDCCH and check a paging message for itself. If thereis a paging message for itself, the UE performs a random accessprocedure to access a network.

For the random access procedure, the MTC UE transmits a preamble througha physical random access channel (PRACH) (S1003), and receives aresponse message (RAR) for the preamble through the MPDCCH and thecorresponding PDSCH. (S1004). In the case of a contention-based randomaccess, the MTC UE may perform a contention resolution procedure such astransmission of an additional PRACH signal (S1005) and reception of theMPDCCH signal and corresponding PDSCH signal (S1006). The signals and/ormessages Msg 1, Msg 2, Msg 3, and Msg 4 transmitted in the RACH processin the MTC may be repeatedly transmitted, and the repeat pattern is setto be different according to the CE level. Msg1 denotes a PRACHpreamble, Msg2 denotes a random access response (RAR), Msg3 denotes ULtransmission on the basis of a UL grant included in the RAR, and Msg4denotes a DL transmission of the BS to Msg3.

For random access, PRACH resources for the different CE levels aresignaled by the BS. This provides the same control of a near-far effecton the PRACH by grouping together UEs experiencing similar path loss. Upto four different PRACH resources may be signaled to the MTC UE.

The MTC UE estimates RSRP using a downlink RS (e.g., CRS, CSI-RS, TRS,and the like), and selects one of different PRACH resources (e.g.,frequency, time, and preamble resources for PRACH) for the random accesson the basis of the measurement result. The RAR for the PRACH and searchspaces for the contention resolution messages for PRACH are alsosignaled at the BS via system information.

The MTC UE that has performed the above-described process may thenreceive an MPDCCH signal and/or a PDSCH signal (S1007) and transmit aphysical uplink shared channel (PUSCH) signal and/or a physical uplinkcontrol channel (PUCCH) (S1108) as a general uplink/downlink signaltransmission process. The MTC UE may transmit uplink control information(UCI) to the BS through the PUCCH or PUSCH. The UCI may includeHARQ-ACK/NACK, scheduling request (SR), and/or CSI.

When RRC connection to the MTC UE is established, the MTC UE monitorsthe MPDCCH in a search space set to acquire uplink and downlink dataallocation and attempts to receive the MDCCH.

In the case of MTC, the MPDCCH and the PDSCH scheduled by the MDCCH aretransmitted/received in different subframes. For example, the MPDCCHhaving the last repetition in subframe #n schedules the PDSCH startingat subframe #n+2. The DCI transmitted by the MPDCCH provides informationon how many times the MPDCCH is repeated so that the MTC UE may knowwhen the PDSCH transmission is started. For example, when the DCI in theMPDCCH started to be transmitted from the subframe #n includesinformation that the MPDCCH is repeated 10 times, a last subframe inwhich the MPDCCH is transmitted is the subframe #n+9 and transmission ofthe PDSCH may start at subframe #n+11.

The PDSCH may be scheduled in the same as or different from a narrowband in which the MPDCCH scheduling the PDSCH is present. If the MPDCCHand the corresponding PDSCH are located in different narrow bands, theMTC UE needs to retune the frequency to the narrow band in which thePDSCH is present before decoding the PDSCH.

For uplink data transmission, scheduling may follow the same timing aslegacy LTE. For example, the MPDCCH which is lastly transmitted atsubframe #n may schedule PUSCH transmission starting at subframe #n+4.

FIG. 28 shows an example of scheduling for MTC and legacy LTE,respectively.

In the legacy LTE, the PDSCH is scheduled using the PDCCH, which usesthe first OFDM symbol(s) in each subframe, and the PDSCH is scheduled inthe same subframe as the subframe in which the PDCCH is received.

In contrast, the MTC PDSCH is cross-subframe scheduled, and one subframebetween the MPDCCH and the PDSCH is used as a time period for MPDCCHdecoding and RF retuning. The MTC control channel and data channel maybe repeated over a large number of subframes including up to 256subframes for the MPDCCH and up to 2048 subframes for the PDSCH so thatthey may be decoded under extreme coverage conditions.

NB-IoT (Narrowband-Internet of Things)

The NB-IoT may refer to a system for supporting low complexity, lowpower consumption through a system bandwidth (system BW) correspondingto one resource block (RB) of a wireless communication system.

Here, NB-IoT may be referred to as other terms such as NB-LTE, NB-IoTenhancement, enhanced NB-IoT, further enhanced NB-IoT, NB-NR. That is,NB-IoT may be replaced with a term defined or to be defined in the 3GPPstandard, and hereinafter, it will be collectively referred to as‘NB-IoT’ for convenience of explanation.

The NB-IoT is a system for supporting a device (or UE) such asmachine-type communication (MTC) in a cellular system so as to be usedas a communication method for implementing IoT (i.e., Internet ofThings). Here, one RB of the existing system band is allocated for theNB-IoT, so that the frequency may be efficiently used. Also, in the caseof NB-IoT, each UE recognizes a single RB as a respective carrier, sothat RB and carrier referred to in connection with NB-IoT in the presentspecification may be interpreted to have the same meaning.

Hereinafter, a frame structure, a physical channel, a multi-carrieroperation, an operation mode, and general signal transmission/receptionrelated to the NB-IoT in the present specification are described inconsideration of the case of the legacy LTE system, but may also beextendedly applied to a next generation system (e.g., an NR system,etc.). In addition, the contents related to NB-IoT in this specificationmay be extendedly applied to MTC (Machine Type Communication) orientedfor similar technical purposes (e.g., low-power, low-cost, coverageenhancement, etc.).

Hereinafter, a case where a transmission time interval of a physicalchannel is a subframe are described as an example. For example, a casewhere a minimum time interval from the start of transmission of onephysical channel (e.g., NPDCCH, NPDSCH, NPUCCH, NPUSCH) to the start oftransmission of a next physical channel is one subframe will bedescribed, but in the following description, the subframe may bereplaced by a slot, a mini-slot, or multiple slots.

Frame Structure and Physical Resource of NB-IoT

First, the NB-IoT frame structure may be configured to be differentaccording to subcarrier spacing. Specifically, FIG. 29 shows an exampleof a frame structure when a subscriber spacing is 15 kHz, and FIG. 30shows an example of a frame structure when a subscriber spacing is 3.75kHz. However, the NB-IoT frame structure is not limited thereto, andNB-IoT for other subscriber spacings (e.g., 30 kHz) may be consideredwith different time/frequency units.

In addition, although the NB-IoT frame structure on the basis of the LTEsystem frame structure has been exemplified in the presentspecification, it is merely for the convenience of explanation and thepresent invention is not limited thereto. The method described in thisdisclosure may also be extendedly applied to NB-IoT based on a framestructure of a next-generation system (e.g., NR system).

Referring to FIG. 29, the NB-IoT frame structure for a 15 kHz subscriberspacing may be configured to be the same as the frame structure of thelegacy system (e.g., LTE system) described above. For example, a 10 msNB-IoT frame may include ten 1 ms NB-IoT subframes, and the 1 ms NB-IoTsubframe may include two 0.5 ms NB-IoT slots. Further, each 0.5 msNB-IoT may include 7 OFDM symbols.

Alternatively, referring to FIG. 30, the 10 ms NB-IoT frame may includefive 2 ms NB-IoT subframes, the 2 ms NB-IoT subframe may include sevenOFDM symbols and one guard period (GP). Also, the 2 ms NB-IoT subframemay be represented by an NB-IoT slot or an NB-IoT RU (resource unit).

Next, physical resources of the NB-IoT for each of downlink and uplinkwill be described.

First, the physical resources of the NB-IoT downlink may be configuredby referring to physical resources of other wireless communicationsystem (e.g., LTE system, NR system, etc.), except that a systembandwidth is limited to a certain number of RBs (e.g., one RB, i.e., 180kHz). For example, when the NB-IoT downlink supports only the 15-kHzsubscriber spacing as described above, the physical resources of theNB-IoT downlink may be configured as resource regions limiting aresource grid of the LTE system shown in FIG. 31 to one RB in thefrequency domain.

Next, in the case of the NB-IoT uplink physical resource, the systembandwidth may be limited to one RB as in the case of downlink. Forexample, if the NB-IoT uplink supports 15 kHz and 3.75 kHz subscriberspacings as described above, a resource grid for the NB-IoT uplink maybe expressed as shown in FIG. 31. In this case, the number ofsubcarriers NULsc and the slot period Tslot in the uplink band in FIG.31 may be given as shown in Table 9 below.

TABLE 9 Subcarrier spacing NULsc Tslot Δf = 3.75 kHz 48  6144 · Ts Δf =15 kHz 12 15360 · Ts

In NB-IoT, resource units (RUs) are used for mapping the PUSCH forNB-IoT (hereinafter referred to as NPUSCH) to resource elements. RU mayinclude NULsymb*NULslot SC-FDMA symbols in the time domain and includeNRUsc number of consecutive subcarriers in the frequency domain. Forexample, NRUsc and NULsymb may be given by Table 10 below for framestructure type 1, which is a frame structure for FDD, and may be givenby Table 11 below for frame structure type 2, which is frame structurefor TDD.

TABLE 10 NPUSCH format Δf NRUsc NULslots NULsymb 1 3.75 kHz 1 16 7  15kHz 1 16 3 8 6 4 12 2 2 3.75 kHz 1 4  15 kHz 1 4

TABLE 11 Supported up- NPUSCH link-downlink format Δf configurationsNRUsc NULslots NULsymb 1 3.75 kHz 1, 4 1 16 7  15 kHz 1, 2, 3, 4, 5 1 163 8 6 4 12 2 2 3.75 kHz 1, 4 1 4  15 kHz 1, 2, 3, 4, 5 1 4

Physical Channel of NB-IoT

A BS and/or a UE supporting the NB-IoT may be configured totransmit/receive physical channels and/or physical signals configuredseparately from the legacy system. Hereinafter, specific contentsrelated to physical channels and/or physical signals supported by theNB-IoT will be described.

An orthogonal frequency division multiple access (OFDMA) scheme may beapplied to the NB-IoT downlink on the basis of a subscriber spacing of15 kHz. Through this, co-existence with other systems (e.g., LTE system,NR system) may be efficiently supported by providing orthogonalitybetween subcarriers. A downlink physical channel/signal of the NB-IoTsystem may be represented by adding ‘N (Narrowband)’ to distinguish itfrom the legacy system. For example, a downlink physical channel may bereferred to as an NPBCH (narrowband physical broadcast channel), anNPDCCH (narrowband physical downlink control channel), or an NPDSCH(narrowband physical downlink shared channel), and a downlink physicalsignal may be referred to as an NPSS (narrowband primary synchronizationsignal), an NSSS (narrowband secondary synchronization signal), an NRS(narrowband reference signal), an NPRS (narrowband positioning referencesignal), an NWUS (narrowband wake up signal), and the like. Generally,the downlink physical channels and physical signals of the NB-IoT may beconfigured to be transmitted on the basis of a time domain multiplexingscheme and/or a frequency domain multiplexing scheme. In the case ofNPBCH, NPDCCH, NPDSCH, etc., which are the downlink channels of theNB-IoT system, repetition transmission may be performed for coverageenhancement. In addition, the NB-IoT uses a newly defined DCI format.For example, the DCI format for NB-IoT may be defined as DCI format N0,DCI format N1, DCI format N2, and the like.

In the NB-IoT uplink, a single carrier frequency division multipleaccess (SC-FDMA) scheme may be applied on the basis of a subscriberspacing of 15 kHz or 3.75 kHz. As mentioned in the downlink section, thephysical channel of the NB-IoT system may be expressed by adding ‘N(Narrowband)’ to distinguish it from the existing system. For example,the uplink physical channel may be represented by a narrowband physicalrandom access channel (NPRACH) or a narrowband physical uplink sharedchannel (NPUSCH), and the uplink physical signal may be represented by anarrowband demodulation reference signal (NDMRS), or the like. NPUSCHmay be divided into NPUSCH format 1 and NPUSCH format 2. In one example,NPUSCH Format 1 may be used for uplink shared channel (UL-SCH)transmission (or transport), and NPUSCH Format 2 may be used for uplinkcontrol information transmission such as HARQ ACK signaling. In the caseof NPRACH, which is an uplink channel of the NB-IoT system, repetitiontransmission may be performed for coverage enhancement. In this case,repetition transmission may be performed by applying frequency hopping.

Multi-Carrier Operation of NB-IoT

Next, a multi-carrier operation of the NB-IoT will be described. Themulticarrier operation may refer to that multiple carriers set fordifferent uses (i.e., different types) are used fortransmitting/receiving channels and/or signals between the BS and/or UEin the NB-lot.

The NB-IoT may operate in a multi-carrier mode. Here, in the NB-IoT, acarrier wave in the N-Iot may be classified as an anchor type carrier(i.e., an anchor carrier, an anchor PRB) and a non-anchor type carrier anon-anchor type carrier (i.e., non-anchor carrier).

The anchor carrier may refer to a carrier that transmits NPSS, NSSS,NPBCH, and NPDSCH for a system information block (N-SIB) for initialaccess from a point of view of the BS. That is, in NB-IoT, the carrierfor initial access may be referred to as an anchor carrier and theother(s) may be referred to as a non-anchor carrier. Here, only oneanchor carrier wave may exist in the system, or there may be a pluralityof anchor carrier waves.

Operation mode of NB-IoT

Next, an operation mode of the NB-IoT will be described. In the NB-IoTsystem, three operation modes may be supported. FIG. 32 shows an exampleof operation modes supported in the NB-IoT system. Although theoperation mode of the NB-IoT is described herein on the basis of an LTEband, this is for convenience of explanation and may be extendedlyapplied to other system bands (e.g. NR system band).

Specifically, FIG. 32(a) shows an example of an in-band system, FIG. 32(b) shows an example of a guard-band system, and FIG. 32(c) Representsan example of a stand-alone system. In this case, the in-band system maybe expressed as an in-band mode, the guard-band system may be expressedas a guard-band mode, and the stand-alone system may be expressed in astand-alone mode.

The in-band system may refer to a system or mode that uses a specific RBin the (legacy) LTE band. The in-band system may be operated byallocating some resource blocks of the LTE system carrier.

A guard-band system may refer to a system or mode that uses NB-IoT in aspace reserved for a guard-band of the legacy LTE band. The guard-bandsystem may be operated by allocating a guard-band of an LTE carrier notused as a resource block in the LTE system. For example, the (legacy)LTE band may be configured to have a guard-band of at least 100 kHz atthe end of each LTE band, and with two non-contiguous guard-bands for200 kHz for NB-IoT may be used.

As described above, the in-band system and the guard-band system may beoperated in a structure in which NB-IoT coexists in the (legacy) LTEband.

By contrast, the stand-alone system may refer to a system or mode thatis configured independently of the legacy LTE band. The stand-alonesystem may be operated by separately allocating frequency bands (e.g.,reassigned GSM carriers in the future) used in a GERAN (GSM EDGE radioaccess network).

The three operation modes described above may be operated independentlyof each other, or two or more operation modes may be operated incombination.

NB-IoT Signal Transmission/Reception Process

FIG. 33 is a diagram illustrating an example of physical channels thatmay be used for NB-IoT and a general signal transmission method usingthe same. In a wireless communication system, an NB-IoT UE may receiveinformation from a BS through a downlink (DL) and the NB-IoT UE maytransmit information to the BS through an uplink (UL). In other words,in the wireless communication system, the BS may transmit information tothe NB-IoT UE through the downlink and the BS may receive informationfrom the NB-IoT UE through the uplink.

The information transmitted/received by the BS and the NB-IoT UEincludes data and various control information, and various physicalchannels may exist depending on the type/purpose of the informationtransmitted/received by the BS and NB-IoT UE. The signaltransmission/reception method of the NB-IoT may be performed by theabove-described wireless communication devices (e.g., BS and UE).

The NB-IoT UE, which is powered on again or enters a new cell, mayperform an initial cell search operation such as adjustingsynchronization with the BS, or the like (SI 1). To this end, the NB-IoTUE receives NPSS and NSSS from the BS, performs synchronization with theBS, and acquires cell identity information. Also, the NB-IoT UE mayreceive the NPBCH from the BS and acquire the in-cell broadcastinformation. In addition, the NB-IoT UE may receive a DL RS (downlinkreference signal) in the initial cell search step to check a downlinkchannel state.

After completion of the initial cell search, the NB-IoT UE may receivethe NPDCCH and the corresponding NPDSCH to acquire more specific systeminformation (S12). In other words, the BS may transmit more specificsystem information by transmitting the NPDCCH and corresponding NPDSCHto the NB-IoT UE after completion of the initial cell search.

Thereafter, the NB-IoT UE may perform a random access procedure tocomplete connection to the BS (S13 to S16).

Specifically, the NB-IoT UE may transmit a preamble to the BS via theNPRACH (S13). As described above, the NPRACH may be configured to berepeatedly transmitted on the basis of frequency hopping or the like toenhance coverage or the like. In other words, the BS may (repeatedly)receive a preamble through the NPRACH from the NB-IoT UE.

Thereafter, the NB-IoT UE may receive a random access response (RAR) forthe preamble from the BS through the NPDCCH and the corresponding NPDSCH(S14). In other words, the BS may transmit the RAR for the preamble tothe NB-IoT UE through the NPDCCH and the corresponding NPDSCH.

Thereafter, the NB-IoT UE transmits the NPUSCH to the BS usingscheduling information in the RAR (S15), and may perform a contentionresolution procedure such as the NPDCCH and the corresponding NPDSCH(S16). In other words, the BS may receive the NPUSCH from the UE usingthe scheduling information in the NB-IoT RAR, and perform the contentionresolution procedure.

The NB-IoT UE that has performed the above-described process may performNPDCCH/NPDSCH reception (S17) and NPUSCH transmission (S18) as a generaluplink/downlink signal transmission process. In other words, afterperforming the above-described processes, the BS may performNPDCCH/NPDSCH transmission and NPUSCH reception as a general signaltransmission/reception process to the NB-IoT UE.

In the case of NB-IoT, as mentioned above, NPBCH, NPDCCH, NPDSCH, andthe like may be repeatedly transmitted for coverage improvement and thelike. In the case of NB-IoT, UL-SCH (i.e., general uplink data) anduplink control information may be transmitted through the NPUSCH. Here,the UL-SCH and the uplink control information (UCI) may be configured tobe transmitted through different NPUSCH formats (e.g., NPUSCH format 1,NPUSCH format 2, etc.).

Also, the UCI may include HARQ ACK/NACK (Hybrid Automatic Repeat andreQuest Acknowledgement/Negative-ACK), SR (Scheduling Request), CSI(Channel State Information), and the like. As described above, the UCIin the NB-IoT may generally be transmitted via the NPUSCH. Also, inresponse to a request/instruction from the network (e.g., BS), the UEmay transmit the UCI via the NPUSCH in a periodic, aperiodic, orsemi-persistent manner.

Hereinafter, the wireless communication system block diagram shown inFIG. 1 will be described in detail.

N. Wireless Communication Device

Referring to FIG. 1, a wireless communication system includes a firstcommunication device 910 and/or a second communication device 920. ‘Aand/or B’ may be interpreted to have the same meaning as ‘includes atleast one of A or B.’ The first communication device may represent a BSand the second communication device may represent a UE (alternatively,the first communication device may represent a UE and the secondcommunication device may represent a BS).

The first and second communication devices may include processors 911and 921, memories 914 and 924, one or more Tx/Rx RF modules 915 and 925,Tx processors 912 and 922, Rx processors 913 and 923, and antennas 916and 926, respectively. The Tx/Rx module is also called a transceiver.The processor implements the functions, procedures and/or methodsdiscussed above. More specifically, in the DL (communication from thefirst communication device to the second communication device), a higherlayer packet from the core network is provided to the processor 911. Theprocessor implements the function of a layer 2 (i.e., L2) layer. In theDL, the processor multiplexes a logical channel and a transport channel,provides radio resource allocation to the second communication device920, and is responsible for signaling to the second communicationdevice. A transmission (TX) processor 912 implements various signalprocessing functions for the L1 layer (i.e., the physical layer). Thesignal processing function facilitates forward error correction (FEC) inthe second communication device, and includes coding and interleaving.The encoded and interleaved signals are scrambled and modulated intocomplex-valued modulation symbols. For modulation, BPSK (QuadraturePhase Shift Keying), QPSK (Quadrature Phase Shift Keying), 16QAM(quadrature amplitude modulation), 64QAM, 246QAM, and the like may beused. The complex-valued modulation symbols (hereinafter referred to asmodulation symbols) are divided into parallel streams, each stream beingmapped to an OFDM subcarrier and multiplexed with a reference signal(RS) in the time and/or frequency domain, and combined together usingIFFT (Inverse Fast Fourier Transform) to create a physical channelcarrying a time domain OFDM symbol stream. The OFDM symbol stream isspatially precoded to produce multiple spatial streams. Each spatialstream may be provided to a different antenna 916 via a separate Tx/Rxmodule (or transceiver, 915). Each Tx/Rx module may upconvert eachspatial stream into an RF carrier for transmission. In the secondcommunication device, each Tx/Rx module (or transceiver, 925) receives asignal of the RF carrier via each antenna 926 of each Tx/Rx module. EachTx/Rx module restores the RF carrier signal to a baseband signal andprovides it to the reception (RX) processor 923. The RX processorimplements various signal processing functions of the L1 (i.e., thephysical layer). The RX processor may perform spatial processing on theinformation to recover any spatial stream directed to the secondcommunication device. If multiple spatial streams are directed to thesecond communication device, they may be combined into a single OFDMAsymbol stream by multiple RX processors. The RX processor transforms theOFDM symbol stream, which is a time domain signal, into a frequencydomain signal using a fast Fourier transform (FFT). The frequency domainsignal includes a separate OFDM symbol stream for each subcarrier of theOFDM signal. The modulation symbols and the reference signal on eachsubcarrier are recovered and demodulated by determining the most likelysignal constellation points sent by the first communication device.These soft decisions may be based on channel estimate values. Softdecisions are decoded and deinterleaved to recover data and controlsignals originally transmitted by the first communication device on thephysical channel. The corresponding data and control signals areprovided to the processor 921.

The UL (communication from the second communication device to the firstcommunication device) is processed in the first communication device 910in a manner similar to that described in connection with a receiverfunction in the second communication device 920. Each Tx/Rx module 925receives a signal via each antenna 926. Each Tx/Rx module provides an RFcarrier and information to RX processor 923. The processor 921 may berelated to the memory 924 that stores program code and data. The memorymay be referred to as a computer-readable medium.

The 5G communication technology discussed above may be applied incombination with the methods proposed in the present disclosure to bedescribed later with reference to FIGS. 34 to 45, or may be used as asupplement to embody or clarify the technical features of the methodsproposed in the present disclosure.

Robot Cleaner

FIGS. 34 and 35 are perspective views of a robot cleaner according to anembodiment of the present invention. FIG. 34 is a perspective view of arobot cleaner when viewed from the upper part, and FIG. 35 is aperspective view of a robot cleaner when viewed from the lower part.FIG. 36 is a block diagram illustrating configuration of a robotcleaner.

Referring to FIGS. 34 to 36, a robot cleaner 100 according to anembodiment of the present invention may include a housing 50, a suctionunit 70, a power supply unit 60, a controller 110, a travel driver 130,a user input unit 140, an event output unit 150, an image acquisitionunit 160, a location recognition unit 170, an obstacle recognition unit180, and a memory 25.

The housing 50 provides a space, on which an internal configuration ismounted, and forms an appearance of the robot cleaner 100.

The power supply unit 60 may include a battery driver and a Li-ionbattery. The battery driver may manage the charging and discharging ofthe Li-ion battery. The Li-ion battery may supply electric power for thedriving of the robot. The Li-ion battery may be configured by connectingtwo 24V/102 A Li-ion batteries in parallel.

The suction unit 70 sucks dust in an area to be cleaned and may use aprinciple of forcing the flow of air using a fan rotating by a motor orthe like.

The controller 110 may include a Micom that manages the power supplyunit 60 including a battery, etc., the obstacle recognition unit 180including various sensors, and the travel driver 130 including aplurality of motors and wheels in hardware of the robot cleaner 100.

The controller 110 may include an application processor (AP) forentirely managing a hardware module system of the of the robot cleaner100. The AP may run an application program for travelling using locationinformation obtained through various sensors and transmit input andoutput information of users to the Micom to drive the motor, etc.Further, the user input unit 140, the image acquisition unit 160, thelocation recognition unit 170, and the like may be managed by the AP.

The robot cleaner 100 may implement functions of object image analysis,object location recognition, and obstacle recognition acquired throughthe image acquisition unit 160 by applying a deep learning model throughan AI device. The robot cleaner 100 may use the following AI device.

FIG. 37 is a block diagram of an AI device according to an embodiment ofthe present invention.

Referring to FIG. 37, an AI device 20 may include a server including anelectronic device or AI module including an AI module capable ofperforming AI processing. The AI device 20 may include as at least somecomponents of the intelligent robot cleaner 100 illustrated in FIG. 36and may perform at least a part of the AI processing.

The AI processing may include all operations related to the control ofthe intelligent robot cleaner 100 illustrated in FIG. 36. For example,the intelligent robot cleaner 100 may perform the AI processing onsensing data or obtained data and perform processing/decision and acontrol signal generation operation. For example, the intelligent robotcleaner 100 may perform the AI processing on data received through acommunication unit and perform the control of an intelligent electronicdevice.

The AI device 20 may be a client device directly using a result of theAI processing, or a device in a cloud environment providing a result ofthe AI processing to another device.

The AI device 20 may include an AI processor 21, a memory 25, and/or acommunication unit 27.

The AI device 20 is a computing device capable of learning a neutralnetwork and may be implemented as various electronic devices including aserver, a desktop PC, a notebook PC, a tablet PC, and the like.

The AI processor 21 may learn a neural network using a program stored inthe memory 25. In particular, the AI processor 21 may learn a neuralnetwork for recognizing data related to the intelligent robot cleaner100. Here, the neural network for recognizing data related to theintelligent robot cleaner 100 may be designed to emulate a human brainstructure on a computer and may include a plurality of network nodeswith weight that emulate neurons in a human neural network. Theplurality of network nodes may send and receive data according to eachconnection relationship so that neurons emulate the synaptic activity ofneurons sending and receiving signals through synapses. Here, the neuralnetwork may include a deep learning model, which has evolved from aneural network model. In the deep learning model, the plurality ofnetwork nodes may be arranged in different layers and may send andreceive data according to a convolution connection relationship.Examples of the neural network model may include various deep learningtechniques, such as deep neural networks (DNN), convolutional deepneural networks (CNN), recurrent Boltzmann machine (RNN), restrictedBoltzmann machine (RBM), deep belief networks (DBN), and deepQ-networks, and are applicable to fields including computer vision,voice recognition, natural language processing, and voice/signalprocessing, etc.

A processor performing the above-described functions may be a generalpurpose processor (e.g., CPU), but may be AI-dedicated processor (e.g.,GPU) for AI learning.

The memory 25 may store various programs and data required for theoperation of the AI device 20. The memory 25 may be implemented as anon-volatile memory, a volatile memory, a flash memory, a hard diskdrive (HDD), or a solid state drive (SSD), etc. The memory 25 may beaccessed by the AI processor 21, and the AI processor 21 mayread/write/modify/delete/update data. Further, the memory 25 may store aneural network model (e.g., deep learning model 26) created by alearning algorithm for data classification/recognition according to anembodiment of the present invention.

The AI processor 21 may further include a data learning unit 22 forlearning a neural network for data classification/recognition. The datalearning unit 22 may learn criteria as to which learning data is used todecide the data classification/recognition and how data is classifiedand recognized using learning data. The data learning unit 22 may learna deep learning model by acquiring learning data to be used in learningand applying the acquired learning data to the deep learning model.

The data learning unit 22 may be manufactured in the form of at leastone hardware chip and mounted on the AI device 20. For example, the datalearning unit 22 may be manufactured in the form of a dedicated hardwarechip for artificial intelligence (AI), or may be manufactured as a partof a general purpose processor (e.g., CPU) or a graphic-dedicatedprocessor (e.g., GPU) and mounted on the AI device 20. Further, the datalearning unit 22 may be implemented as a software module. If the datalearning unit 22 is implemented as the software module (or a programmodule including instruction), the software module may be stored innon-transitory computer readable media. In this case, at least onesoftware module may be provided by an operating system (OS), or providedby an application.

The data learning unit 22 may include a learning data acquisition unit23 and a model learning unit 24.

The learning data acquisition unit 23 may acquire learning data requiredfor a neural network model for classifying and recognizing data. Forexample, the learning data acquisition unit 23 may acquire data and/orsample data of a mobile terminal 10 for inputting to the neural networkmodel as learning data.

By using the acquired learning data, the model learning unit 24 maylearn so that the neural network model has a criteria for determininghow to classify predetermined data. In this instance, the model learningunit 24 may train the neural network model through supervised learningwhich uses at least a part of the learning data as the criteria fordetermination. Alternatively, the model learning unit 24 may train theneural network model through unsupervised learning which finds criteriafor determination by allowing the neural network model to learn on itsown using the learning data without supervision. Further, the modellearning unit 24 may train the neural network model throughreinforcement learning using feedback about whether a right decision ismade on a situation by learning. Further, the model learning unit 24 maytrain the neural network model using a learning algorithm includingerror back-propagation or gradient descent.

If the neural network model is trained, the model learning unit 24 maystore the trained neural network model in the memory. The model learningunit 24 may store the trained neural network model in a memory of aserver connected to the AI device 20 over a wired or wireless network.

The data learning unit 22 may further include a learning datapreprocessing unit (not shown) and a learning data selection unit (notshown), in order to improve a result of analysis of a recognition modelor save resources or time required to create the recognition model.

The learning data preprocessing unit may preprocess obtained data sothat the obtained data can be used in learning for deciding thesituation. For example, the learning data preprocessing unit may processobtained learning data into a predetermined format so that he modellearning unit 24 can use the obtained learning data in learning forrecognizing images.

Moreover, the learning data selection unit may select data required forlearning among learning data obtained by the learning data acquisitionunit 23 or learning data preprocessed by the preprocessing unit. Theselected learning data may be provided to the model learning unit 24.For example, the learning data selection unit may detect a specific areafrom an image acquired by the image acquisition unit 160 of the robotcleaner 100, thereby selecting only data for an object included in thespecific area as learning data.

In addition, the data learning unit 22 may further include a modelevaluation unit (not shown) for improving the result of analysis of theneural network model.

The model evaluation unit may input evaluation data to the neuralnetwork model and may allow the model learning unit 22 to learn theneural network model again if a result of analysis output from theevaluation data does not satisfy a predetermined criterion. In thiscase, the evaluation data may be data that is pre-defined for evaluatingthe recognition model. For example, if the number or a proportion ofevaluation data with inaccurate analysis result among analysis resultsof the recognition model learned on the evaluation data exceeds apredetermined threshold, the model evaluation unit may evaluate theanalysis result as not satisfying the predetermined criterion.

The communication unit 27 may transmit, to an external electronicdevice, a result of the AI processing by the AI processor 21. Forexample, the external electronic device may include a Bluetooth device,a self-driving vehicle, a robot, a drone, an AR device, a mobile device,household appliances, and the like.

For example, if the external electronic device is a self-drivingvehicle, the AI device 20 may be defined as another vehiclecommunicating with the self-driving module vehicle, or 5G network. TheAI device 20 may be implemented to be functionally embedded in theself-driving module included in the vehicle. Further, the 5G network mayinclude a server or a module performing a self-driving related control.

Although the AI device 20 illustrated in FIG. 37 has been described tobe functionally divided into the AI processor 21, the memory 25, thecommunication unit 27, etc., the above components may be integrated intoone module and referred to as an AI module.

The robot cleaner 100 can implement at least one of the above-describedfunctions by receiving a result of the AI processing from an externalserver through the communication unit.

The travel driver 130 includes a wheel motor 131 and a driving wheel 61.The driving wheel 61 includes first and second driving wheels 61 a and61 b. The first and second driving wheels 61 a and 61 b are controlledby the wheel motor 131, and the wheel motor 131 is driven by the controlof the travel driver 130. The wheel motor 131 connected to the first andsecond driving wheels 61 a and 61 b may be individually separated. Thus,the first and second driving wheels 61 a and 61 b can operateindependently of each other. Hence, the robot cleaner 100 can rotateforward or backward as well as in any one direction.

The user input unit 140 forward, to the controller 110, various controlcommands or information that are previously set depending on amanipulation and an input of the user. The user input unit 140 may beimplemented as a menu-key or an input panel installed on the left sideof a display device, or a remote controller separated from the robotcleaner 100. Alternatively, a part of configuration of the user inputunit 140 may be implemented to be integrated with a display unit 152. Ifthe display unit 152 is a touch screen, the user may forward apredetermined command to the controller 110 by touching an input menudisplayed on the display unit 152.

The user input unit 140 may sense a gesture of the user through a sensorfor sensing an area and forward a command of the user to the controller110. The user input unit 140 may forward a voice command of the user tothe controller 110 and perform operations and settings.

The event output unit 150 is configured to extract an object from animage acquired by the image acquisition unit 160 and to inform the userof an event situation if the event situation occurs. The event outputunit 150 may include a voice output unit 151 and the display unit 152.The voice output 151 outputs a voice message that is previously storedwhen a specific event occurs. The display unit 152 displays previouslystored texts or images when a specific event occurs. The display unit152 may display a driving state of the robot cleaner 100 or displayadditional information such as date/time/temperature/humidity of acurrent state.

The image acquisition unit 160 may include a 2D camera 161 and an RGBDcamera 162. The 2D camera 161 may be a sensor for recognizing a personor an object based on a 2D image. The RGBD (Red, Green, Blue, Distance)camera 162 may be a sensor for detecting a person or an object usingcaptured images having depth data obtained from a camera having RGBDsensors or other similar 3D imaging devices.

The image acquisition unit 160 acquires an image on the travel path ofthe robot cleaner 100 and provides acquired image data to the controller110. The controller 110 may reset the travel path based on this.

The location recognition unit 170 may include a light detection andranging (LiDAR) 171 and a simultaneous localization and mapping (SLAM)camera 172. The SLAM camera 172 can implement simultaneous locationtracking and mapping technology. The robot cleaner 100 may detectsurrounding information using the SLAM camera 172 and process theobtained information to thereby create a map corresponding to a taskexecution space and at the same time estimate its own absolute location.The LiDAR 171 is a laser radar and may also be a sensor that irradiatesa laser beam and collects and analyzes backscattered light among lightabsorbed or scattered by aerosol to perform location recognition. Thelocation recognition unit 170 may process sensing data collected by theLiDAR 171 and the SLAM camera 172, etc. and may be responsible for datamanagement for the location recognition and the obstacle recognition ofthe robot cleaner 100.

The obstacle recognition unit 180 may include an infrared (IR) remotecontrol receiver 181, an ultrasonic sensor (USS) 182, a cliff PSD 183,an attitude reference system (ARS) 184, a bumper 185, and an opticalflow sensor (OFS) 186. The IR remote control receiver 181 may include asensor that receives a signal of an IR remote control for remotelycontrolling the robot cleaner 100. The USS 182 may include a sensor thatdecides a distance between an obstacle and the robot cleaner using anultrasonic signal. The cliff PSD 183 may include a sensor that senses acliff or a bluff, etc. in a range of travel of the robot cleaner 100 inall directions of 360 degrees. The ARS 184 may include a sensor that candetect an attitude of the robot cleaner. The ARS 184 may include asensor consisting of 3-axis accelerometer and 3-axis gyroscope thatdetect an amount of rotation of the robot cleaner 100. The bumper 185may include a sensor that senses a collision between the robot cleaner100 and the obstacle. The sensor included in the bumper 185 may sensethe collision between the robot cleaner 100 and the obstacle in the 360degree range. The OFS 186 may include a sensor that can sense aphenomenon, in which wheels of the robot cleaner 100 spin during travelof the robot cleaner 100, and measure a travel distance of the robotcleaner 100 on various floor surfaces.

Robot Cleaner Managing Method

FIG. 38 is a flow chart illustrating a method of managing a robotcleaner according to a first embodiment.

Referring to the above drawings and FIG. 38, a method of managing arobot cleaner according to the present invention is described asfollows.

First, in a first step S110, the robot cleaner 100 obtains an image on atravel path while moving along the travel path.

FIG. 39 illustrates an embodiment in which a robot cleaner selects atravel path on a cleaning map.

Referring to FIG. 39, a cleaning map CM may include multiple cells Cregularly arranged on 2D. The multiple cells C may be distinguished byunique position coordinates which are represented by 2D coordinates. Forexample, each cell C may have unique coordinates, or each edge of thecells C may have unique coordinates. A width of the cell C on thecleaning map CM may be set to a width at which the cleaning is performedwhile the robot cleaner 100 moves, and a size of the cell C is notlimited thereto.

The robot cleaner 100 sequentially travels the respective cells C from astart position SP to an end position EP and passes all the cells C onthe cleaning map CM. More specifically, the robot cleaner 100 crossesfrom the start position SP along a first direction (e.g., x-axisdirection) and then moves by one cell C in a second direction (e.g.,y-axis direction). Then, the robot cleaner 100 crosses again in thefirst direction. Through the above-described method, the robot cleaner100 gradually goes from one side of the cleaning map CM toward theopposite side and moves up to the end position EP.

In a second step S120, the controller 110 of the robot cleaner 100decides whether or not an object is present in the image.

To this end, the robot cleaner 100 continuously acquires an image on atravel path PASS through the image acquisition unit 160. The controller110 decides whether or not an object is present in the image. FIG. 40illustrates an example of an image acquired by the image acquisitionunit 160.

The controller 110 detects an edge of an image to extract an object Subin the image. The controller 110 may use Sobel Mask, Prewitt Mask, orRobert Mask, etc. to detect the edge. The controller 110 may determinean outermost edge among the detected edges as an outline of the objectSub.

In a third step S130 and a fourth step S140, the controller 110classifies a type of an object when the object has been found. Thecontroller 110 decides whether or not the classified object Sub is anavoidance object.

To this end, the controller 110 checks whether image features such asthe outline and features of the object Sub are matched to image featuresstored in the memory 25. The object Sub is classified as an avoidanceobject or an ignorance object, and information on image features of eachof the avoidance object and the ignorance object may be stored in thememory 25. The following Table 12 indicates an example of imageinformation of the avoidance object stored in the memory 25.

TABLE 12 Avoidance Object Image Information Immovable Object Sofa DATA1Table DATA2 Fragile Object Bottle DATA3 Cup DATA4 Contaminants Sauce 1DATA5 Feces 1 DATA6 No-Suction Object Accessory DATA7 Key DATA8

Referring to Table 12, the avoidance object may be classified as one ofan immovable object, a fragile object, a contaminant, and a no-suctionobject.

The immovable object refers to an object that cannot be moved by adriving force with which the robot cleaner 100 travels. For example, theimmovable object may be a sofa or a table. The fragile object may be abottle or a cup made of glass.

The contaminants correspond to viscous or liquid substances, such assauces and companion animal feces. Image features of the contaminantsmay not be uniform. The controller 110 may decide whether or not theobject Sub is the contaminants in consideration of a shape andtransparency of the object Sub.

The no-suction object is an object that does not want to be suck by thesuction unit 70 of the robot cleaner 100 and refers to things that arenot subject to cleaning. For example, the no-suction object may includevaluables. In addition to the valuables, the no-suction object mayinclude small objects, for example, button, small accessory, key, etc.that may often be left in the area to be cleaned.

In the process of classifying the object Sub, criteria for determiningthe similarity between the image features of the object Sub and theimage features stored in the memory 25 may vary depending on the type ofthe avoidance object.

In order to avoid the fragile object and the contaminants as far aspossible, the criteria for determining the similarity may be set to below. That is, even if the similarity between the image features of theobject Sub and the fragile object and the contaminants stored in thememory 25 is somewhat low, the controller 110 may define thecorresponding object Sub as the avoidance object.

The criteria of the no-suction object may vary depending on each object.For example, the criteria for determining the similarity of valuablesand the like may be lowered, and the criteria for determining thesimilarity of trivial items may be raised.

The criteria for determining the similarity of the immovable object maybe set to be very high. If the robot cleaner 100 is incapable of runningduring moving on a cell C with the object Sub that is not decided as theimmovable object, the controller 110 may set a bypass travel path inorder to avoid the corresponding object Sub.

The controller 110 may decide the object Sub, that makes the robotcleaner 100 in a state where the robot cleaner 100 is incapable ofrunning, as the immovable object and may store the corresponding imagein the memory 25. Thus, if the corresponding object Sub is extracted ina subsequent image, the controller 110 may decide it as the immovableobject.

If the object Sub corresponds to a lightweight doll that does notdisturb the movement of the robot cleaner 100, the controller 110performs a learning process so that the corresponding object Sub can benaturally exempted from the avoidance object. That is, the avoidanceobject may be defined for some objects Sub.

A basic algorithm of the controller 110 defines an avoidance object andregards all objects Sub other than the avoidance object as an ignoranceobject. Thus, the object Sub defined as the ignorance object may beregarded as an exceptional object of processing. A reason to select someobjects Sub as the ignorance objects as described above is that theobject Sub can be avoided through the obstacle recognition unit 180 inaddition to the image reading. The controller 110 may be configured toavoid all relatively large-sized objects, such as a doll, according to aresult of the image reading of the obstacle recognition unit 180.According to the above-described method, the robot cleaner 100 travelsby avoiding even a large-sized light object, such as a doll, and thusthe efficiency of the cleaning may be reduced.

The present invention pushes an object Sub regarded as the ignoranceobject through the image reading while the travel of the robot cleaner,and thus can clean a cell on which the corresponding object Sub isdisposed.

In a fifth step S150, if an object Sub is the avoidance object, thecontroller 110 determines a bypass travel path capable of avoiding theavoidance object.

FIG. 41 illustrates an example of setting a bypass travel path. Morespecifically, FIG. 41 illustrates a travel path that is configured sothat a robot cleaner sequentially passes a cell C(Xn, Yn) and a cellC(Xn, Yn−1) via a cell C(Xn, Yn+1).

Referring to FIG. 41, if an object Sub extracted from an image isdecided as an avoidance object, the controller 110 sets a cell of acleaning map CM, on which the object Sub is positioned, as an avoidancearea.

The controller 110 moves up to a cell C(Xn, Yn+1) and then selects andmoves to a cell in a direction vertical to a travel path PASS. Forexample, as illustrated in FIG. 41, if the avoidance area is positionedon the travel path PASS moving along the y-axis direction, thecontroller 110 modifies a travel path so that it moves up to the cellC(Xn, Yn+1) and then moves along the x-axis direction. Further, thecontroller 110 moves up to a cell C(Xn−1, Yn−1) completely via a cellC(Xn, Yn) on the y-axis and then moves to a cell C(Xn, Yn−1).

If the object is not the avoidance object as a result of the fourth stepS140, the controller 110, the controller 110 is configured to repeat thefirst step S110. That is, the controller 110 performs an operation ofobtaining an image on the travel path PASS while moving along a travelpath on which it is currently moving.

As described above, the robot cleaner 100 repeats the operation from thefirst step S110 to the fifth step S150 until it moves on all the cells Con the cleaning map CM.

The first embodiment described that the robot cleaner 100 itself resetsautonomously the travel path.

When the robot cleaner 100 has founded an object Sub decided as theavoidance object, the robot cleaner 100 may perform an operation ofinforming about the discovery of the avoidance object, in order toefficiently cope with it. A method of processing a discovery area of anavoidance object based on an event while informing about the even forthe discovery of the avoidance object is described as follows.

FIG. 42 is a flow chart illustrating a method of managing a robotcleaner according to a second embodiment.

Referring to FIG. 42, in a method of managing a robot cleaner accordingto a second embodiment, a first step S210 corresponds to an operationincluding the first step S110 to the third step S130 of FIG. 36according to the first embodiment. A second step S220 according to thesecond embodiment is substantially the same as the fourth step S140according to the first embodiment. Thus, a detailed description of thefirst step S210 and the second step S220 is omitted in the secondembodiment.

In a third step S230, if an object Sub is an avoidance object, a robotcleaner 100 informs the user of the fact that the avoidance object hasbeen founded.

FIG. 43 illustrates an example of a method of informing of an avoidanceobject.

Referring to FIG. 43, when an avoidance object has been founded, therobot cleaner 100 may display a text, that the avoidance object has beenfounded, through a display unit 152. When an avoidance object has beenfounded, the robot cleaner 100 may output a message or an alarm, thatthe avoidance object has been founded, through a voice output unit 151.

In a fourth step S240, the robot cleaner 100 prepares to receive auser's instruction while informing of the fact that the avoidance objecthas been founded. The robot cleaner 100 may be in a stopped state whilewaiting for the user's instruction. The robot cleaner 100 may receive auser voice signal through a user input unit 140.

If the robot cleaner 100 fails to receive a user's response for apredetermined period of time, the robot cleaner 100 sets a bypass travelpath.

In a fifth step S250, the robot cleaner 100 reads an instruction fromthe user as “Avoid the avoidance object” or “Ignore the avoidanceobject”.

The robot cleaner 100 performs an operation of the first step S210 inresponse to the instruction of “Ignore the avoidance object”. That is,even if the robot cleaner 100 has decided an object Sub of an image asan avoidance object, the robot cleaner 100 preferentially receives auser's instruction, ignores the corresponding object Sub, and maintainsan existing travel path PASS.

In a sixth step S260, the robot cleaner 100 sets a bypass travel path inresponse to the instruction of “Avoid the avoidance object” from theuser.

A method of setting the bypass travel path may equally use the methoddescribed in the first embodiment.

In the present invention, the no-suction object, that the controller 110classifies as the avoidance object, may be an object that is temporarilyout of the occupation of the user. In particular, the no-suction objectmay be a lost article, such as a remote control or a key, where the usertemporarily forgets the location of the objects.

Since the robot cleaner 100 regards a residential space to be cleaned asa cleaning map CM, it can recognize a location in the residential space.In particular, the robot cleaner 100 according to the present inventionmay recognize an object Sub based on an image obtained during themovement. Based on this, the robot cleaner 100 according to the presentinvention can provide additional services in addition to a propercleaning task. For example, the robot cleaner 100 can help inidentifying a location of a lost article as follows.

In order to identify the location of the lost article, the robot cleaner100 may classify an object Sub based on an image obtained during themovement and store location information of the corresponding object Subin a memory 25 as indicated in the following Table 13.

TABLE 13 Cell Location Object Type Information Information Time KeyC(X2, Y2) In front of the door 2019.03.01/20:00 Remote Control C(X5,Y10) Under the sofa 2019.03.02/21:00 Ring C(X32, Y44) In front of thecloset 2019.03.03/19:00

Referring to Table 13, the object type is a name of the object Subclassified based on the image. The “cell information” refers to alocation where the corresponding object Sub is found on the cleaning mapCM. The location information is information obtained by matching alocation of a cell where the corresponding object Sub is found to fixedobjects in an area to be cleaned. The time refers to the most recenttime at which the objects Sub were found.

FIG. 44 illustrates a method for identifying a lost article using arobot cleaner.

Referring to FIG. 44, the robot cleaner 100 may receive “lost articlelocation identification request” from a user USER through voicerecognition or other commands.

The robot cleaner 100 provides “lost article location notice” inresponse to the “lost article location identification request”. The“lost article location notice” may use a method such as a voice signalusing the voice output unit 151 or a text display using the display unit152.

Robot Cleaner Management System Using Server

The above embodiments have been described focusing on the robot cleaner100 including the image acquisition unit 160 for acquiring an image andthe memory 25 for storing image information of an object Sub.

Embodiments of the present invention may be configured such that someconfiguration of the robot cleaner 100 is distributed to the outside oris implemented as a system using an external device.

FIG. 45 illustrates a management system of a robot cleaner according toanother embodiment.

Referring to FIG. 45, a management system of a robot cleaner includes arobot cleaner 100, a server 300, a photographing means 400, and a mobileterminal 500.

The robot cleaner 100 can perform the cleaning while moving on a travelpath, in the same manner as the above-described embodiments. The robotcleaner 100 may have the same configuration as the robot cleaner 100described with reference to FIGS. 34 to 36, or omit some configuration.For example, the image acquisition unit 160 of the robot cleaner 100 maybe replaced by the photographing means 400, and at least a part ofconfiguration of the user input unit 140 may be replaced by the mobileterminal 500. The memory 25 may be replaced by the server 300, or theserver 300 may be used as part of the memory 25.

The robot cleaner 100 may transmit and receive signals to and from theserver 300 or the mobile terminal 500. For example, the robot cleaner100 may transmit and receive information of a cleaning map CM, etc. toand from the server 300. Further, the robot cleaner 100 may receive acaptured image of an area to be cleaned from the photographing means400. Thus, the robot cleaner 100 may combine an image captured by itselfthrough the image acquisition unit 160 and the image received from thephotographing means 400, monitor the area to be cleaned, and extract anobject. The robot cleaner 100 may be controlled according to a commandreceived from the server 300 or the mobile terminal 500, in addition toreceiving a command directly from the user through the user input unit140.

The server 300 may receive information from the robot cleaner 100, thephotographing means 400, and/or the mobile terminal 500. The server 300may combine the received information and store and manage the combinedinformation. For example, the server 300 may store an avoidance objectand image information matched to the avoidance object as indicated inthe above Table 12. Further, the server 300 may store locationinformation of an object obtained during the movement of the robotcleaner 100 as indicated in the above Table 13.

The server 300 may transmit stored information to the robot cleaner 100or the mobile terminal 500. For example, the server 300 may provideimage information of the avoidance object to the robot cleaner 100 asindicated in the above Table 12. Further, the server 300 may storelocation information of an object in the robot cleaner 100 as indicatedin the above Table 13.

The server 300 may receive images from multiple robot cleaners 100 andprovide information stored in the server 300 to the multiple robotcleaners 100. That is, since an AI processor 111 of the robot cleaner100 performs a learning based on more information, the accuracy ofclassifying objects can be increased.

The photographing means 400 may include a camera installed around anarea to be cleaned. For example, the photographing means 400 may be aclosed circuit television (CCTV) camera. The photographing means 400 maysend captured images to the server 300 or the robot cleaner 100.

The mobile terminal 500 may transmit and receive data to and from theserver 300. For example, the mobile terminal 500 may transmit an imageof an area to be cleaned to the server 300, or may directly selectimages of an avoidance object and an ignorance object and transmit them.Further, the mobile terminal 500 may transmit and receive data to andfrom the robot cleaner 100. For example, the mobile terminal 500 mayforward a call signal for calling the robot cleaner 100 or a specificinstruction for an event occurrence. The robot cleaner 100 may perform aspecific operation or modify a travel path in response to the callsignal received from the mobile terminal 500.

The configurations described in the present disclosure are merely anexample and are not to be considered as limiting the present invention.The scope of the present invention should be determined by rationalinterpretation of the appended claims, and all changes within theequivalent range of the present invention are included in the scope ofthe present invention.

1. An intelligent robot cleaner setting a travel path based on a videolearning, the intelligent robot cleaner comprising: a travel driverconfigured to move to an area to be cleaned along the travel path; asuction unit configured to suck foreign substances on the travel path;an image acquisition unit configured to acquire an image on the travelpath; and a controller configured to analyze the image, decide whetheran object is present on the travel path, classify a type of the object,and set a bypass travel path that avoids the object if the object is anavoidance object.
 2. The intelligent robot cleaner of claim 1, furthercomprising a memory configured to store image information of theavoidance object, wherein the controller is configured to check whetheran image feature of an object extracted from the image is matched toimage information of the avoidance object stored in the memory.
 3. Theintelligent robot cleaner of claim 2, wherein the memory stores, as theimage information of the avoidance object, an image of at least one ofan immovable object, a fragile object, a viscous or liquid contaminant,or a no-suction object.
 4. The intelligent robot cleaner of claim 3,wherein the controller is configured to classify the object as anignorance object if the object does not belong to the avoidance object,and maintain the travel path.
 5. The intelligent robot cleaner of claim4, wherein the controller is configured to maintain the travel path ifthe object is a movable object due to the movement of the robot cleaner.6. The intelligent robot cleaner of claim 3, further comprising an eventoutput unit configured to output an event that the avoidance object hasbeen found if the controller finds the avoidance object.
 7. Theintelligent robot cleaner of claim 6, further comprising a user inputunit configured to receive a processing instruction corresponding to theevent.
 8. The intelligent robot cleaner of claim 7, wherein if the eventis output and then an instruction of ignoring the avoidance object isreceived from the user input unit, the controller is configured tocontrol the travel driver so that the travel driver travels on an areain which the avoidance object is found.
 9. The intelligent robot cleanerof claim 7, wherein if the event is output and then a processinginstruction for the avoidance object is not received from the user inputunit for a predetermined period of time, the controller is configured toset the bypass travel path.
 10. The intelligent robot cleaner of claim3, wherein if the controller decides the object as the no-suctionobject, the controller is configured to store, in the memory, a name andlocation information of the no-suction object in the acquired image. 11.A method of managing an intelligent robot cleaner setting a travel pathbased on a video learning, the method comprising: acquiring an image onthe travel path; analyzing the image and deciding whether an object ispresent on the travel path; classifying a type of the object if theobject is present; and setting a bypass travel path that bypasses thetravel path if the classified object is an avoidance object.
 12. Themethod of claim 11, wherein the classifying of the type of the object isdetermined based on a result of learning the acquired image.
 13. Themethod of claim 12, wherein the classifying of the object comprisesclassifying the object as the avoidance object if the object is animmovable object, a fragile object, a viscous or liquid contaminant, ora no-suction object.
 14. The method of claim 13, wherein the classifyingof the object further comprises: classifying the object as the avoidanceobject or an ignorance object and classifying the object as theignorance object if the object does not belong to the avoidance object;and maintaining the travel path if the classified object is theignorance object.
 15. The method of claim 14, wherein the classifying ofthe object further comprises classifying the object as the ignoranceobject if the object is a movable object due to the movement of therobot cleaner.
 16. The method of claim 13, further comprising, if theobject is the avoidance object, outputting an event that the avoidanceobject has been found.
 17. The method of claim 16, further comprising,after outputting the event that the avoidance object has been found,preparing to receive a processing instruction corresponding to theevent.
 18. The method of claim 17, further comprising, if the processinginstruction corresponding to the event is an instruction of ignoring theavoidance object, traveling on an area in which the avoidance object isfound.
 19. The method of claim 17, further comprising, if the processinginstruction corresponding to the event is not received for apredetermined period of time, setting the bypass travel path.
 20. Themethod of claim 13, further comprising, if the object is classified asthe no-suction object in the classifying of the object, storing a nameand location information of the no-suction object.